DEFINITIONS"Factor H Binding Protein" (fHbp), which is also known in the literature as GNA1870, GNA 1870, ORF2086, LP2086 (lipoprotein 2086), and "741" refers to a class ofN. meningitidis polypeptides. It is found in nature as a lipoprotein on the surface of the bacteriumN.meningitidis. fHbps have been sub-divided into three fHbp variant groups (referred to as variant group 1 (v.1), variant group 2 (v.2), and variant group 3 (v.3) in some reports (Masignani et al. (2003) J Exp Med 197:789-99) and sub-family A and B in other reports (see, e.g.,Fletcher et al. (2004) Infect Immun 72:2088-2100)) based on amino acid sequence variability and immunologic cross-reactivity (Masignani et al. (2003) J Exp Med 197:789-99). fHbp also can be classified into one of the six most common fHbp modular groups, designated Modular Group I to Modular Group VI, as shown inFigure 2 ofVu et al. (2012) Sci. Reports 2:341. Each unique fHbp found inN. meningitidis is also assigned an fHbp peptide ID according to the pubmlst.org/neisseria/fHbp/ website. Because the length of variant 2 (v.2) fHbp protein (from strain 8047, fHbp ID 77) and variant 3 (v.3) fHbp (from strain M1239, fHbp ID 28) differ by -1 and +7 amino acid residues, respectively, from that from strain MC58 (fHbp ID 1), the numbering used herein to refer to residues for v.2 and v.3 fHbp proteins differs from numbering based on the actual amino acid sequences of these proteins. Thus, for example, reference to a leucine residue (L) at position 166 of the v.2 or v.3 fHbp sequence refers to the residue at position 165 of the v.2 protein and at position 173 in the v.3 protein. Unless noted otherwise, the numbering of the amino acid substitutions present in the fHbp variants is with reference to the numbering of the amino acid residues in fHbp ID 1.
Human factor H ("human fH") as used herein, refers to a protein comprising an amino acid sequence as shown inFigure 18 (SEQ ID NO:4), and naturally-occurring human allelic variants thereof.
"Derived from" in the context of an amino acid sequence or polynucleotide sequence (e.g., an amino acid sequence "derived from" fHbp ID 1) is meant to indicate that the polypeptide or nucleic acid has a sequence that is based on that of a reference polypeptide or nucleic acid (e.g., a naturally occurring fHbp protein or encoding nucleic acid), and is not meant to be limiting as to the source or method in which the protein or nucleic acid is made. Non-limiting examples of reference polypeptides and reference polynucleotides from which an amino acid sequence or polynucleotide sequence may be "derived from" include a naturally-occurring fHbp, fHbp ID 1, and a non-naturally-occurring fHbp. "Derived from" in the context of bacterial strains is meant to indicate that a strain was obtained through passagein vivo, or inin vitro culture, of a parental strain and/or is a recombinant cell obtained by modification of a parental strain.
"Conservative amino acid substitution" refers to a substitution of one amino acid residue for another sharing chemical and physical properties of the amino acid side chain (e.g., charge, size, hydrophobicity/hydrophilicity). "Conservative substitutions" are intended to include substitution within the following groups of amino acid residues: gly, ala; val, ile, leu; asp, glu; asn, gln; ser, thr; lys, arg; and phe, tyr. Guidance for such substitutions can be drawn from alignments of amino acid sequences of polypeptides presenting the epitope of interest.
The term "protective immunity" means that a vaccine or immunization schedule that is administered to a mammal induces an immune response that prevents, retards the development of, or reduces the severity of a disease that is caused byNeisseria meningitidis, or diminishes or altogether eliminates the symptoms of the disease. Protective immunity can be accompanied by production of bactericidal antibodies. It should be noted that production of bactericidal antibodies againstNeisseria meningitidis is accepted in the field as predictive of a vaccine's protective effect in humans. (Goldschneider et al. (1969) J. Exp. Med. 129:1307;Borrow et al. (2001) Infect Immun. 69:1568).
The phrase "a disease caused by a strain ofNeisseria meningitidis" encompasses any clinical symptom or combination of clinical symptoms that are present in an infection of a human with aNeisseria meningitidis. These symptoms include but are not limited to: colonization of the upper respiratory tract (e.g. mucosa of the nasopharynx and tonsils) by a pathogenic strain ofNeisseria meningitidis, penetration of the bacteria into the mucosa and the submucosal vascular bed, septicemia, septic shock, inflammation, hemorrhagic skin lesions, activation of fibrinolysis and of blood coagulation, organ dysfunction such as kidney, lung, and cardiac failure, adrenal hemorrhaging and muscular infarction, capillary leakage, edema, peripheral limb ischemia, respiratory distress syndrome, pericarditis and meningitis.
The phrase "specifically binds to an antibody" or "specifically immunoreactive with", in the context of an antigen (e.g., a polypeptide antigen) refers to a binding reaction that is based on and/or is probative of the presence of the antigen in a sample which may also include a heterogeneous population of other molecules. Thus, under designated conditions, the specified antibody or antibodies bind(s) to a particular antigen or antigens in a sample and do not bind in a significant amount to other molecules present in the sample. "Specifically binds to an antibody" or "specifically immunoreactive with" in the context of an epitope of an antigen (e.g., an epitope of a polypeptide) refers to a binding reaction which is based on and/or is probative of the presence of the epitope in an antigen (e.g., polypeptide) which may also include a heterogeneous population of other epitopes, as well as a heterogeneous population of antigens. Thus, under designated conditions, the specified antibody or antibodies bind(s) to a particular epitope of an antigen and do not bind in a significant amount to other epitopes present in the antigen and/or in the sample.
The phrase "in a sufficient amount to elicit an immune response" means that there is a detectable difference between an immune response indicator measured before and after administration of a particular antigen preparation. Immune response indicators include but are not limited to: antibody titer or specificity, as detected by an assay such as enzyme-linked immunosorbent assay (ELISA), bactericidal assay, flow cytometry, immunoprecipitation, Ouchterlony immunodiffusion; binding detection assays of, for example, spot, Western blot or antigen arrays; cytotoxicity assays, etc.
A "surface antigen" is an antigen that is present in a surface structure ofNeisseria meningitidis (e.g. the outer membrane, capsule, pili, etc.).
"Isolated" refers to an entity of interest that is in an environment different from that in which the compound may naturally occur. "Isolated" is meant to include compounds that are within samples that are substantially enriched for the compound of interest and/or in which the compound of interest is partially or substantially purified. In some cases, an isolated component (e.g., a polypeptide, such as an fHbp variant of the present disclosure; a nucleic acid of the present disclosure; a recombinant vector of the present disclosure) is purified, e.g., the isolated component is at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or greater than 99%, pure.
"Enriched" means that a sample is non-naturally manipulated (e.g., by an experimentalist or a clinician) so that a compound of interest is present in a greater concentration (e.g., at least a three-fold greater, at least 4-fold greater, at least 8-fold greater, at least 64-fold greater, or more) than the concentration of the compound in the starting sample, such as a biological sample (e.g., a sample in which the compound naturally occurs or in which it is present after administration), or in which the compound was made (e.g., as in a bacterial polypeptide, antibody, nucleic acid, and the like).
Before the present invention is further described, it is to be understood that this invention is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.
Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges, and are also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.
It must be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a factor H binding protein" includes a plurality of such factor H binding proteins and reference to "the immunogenic composition" includes reference to one or more immunogenic compositions and equivalents thereof known to those skilled in the art, and so forth. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only" and the like in connection with the recitation of claim elements, or use of a "negative" limitation.
It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. All combinations of the embodiments pertaining to the invention are specifically embraced by the present invention and are disclosed herein just as if each and every combination was individually and explicitly disclosed. In addition, all sub-combinations of the various embodiments and elements thereof are also specifically embraced by the present invention and are disclosed herein just as if each and every such sub-combination was individually and explicitly disclosed herein.
The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.
DETAILED DESCRIPTIONThe present disclosure provides variant factor H binding proteins (fHbp) that can elicit antibodies that are bactericidal for at least one strain ofNeisseria meningitidis. The present disclosure provides compositions, including immunogenic compositions, comprising a variant fHbp of the present disclosure. The present disclosure provides methods of use of variant fHbp of the present disclosure, or a composition comprising a variant fHbp of the present disclosure.
VARIANT FHBPThe present disclosure provides variant fHbp that differ in amino acid sequence from a wild-typeN. meningitidis fHbp by from 1 to 10 amino acids (e.g., by from 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids) from 10 amino acids to 15 amino acids, from 15 amino acids to 20 amino acids, from 20 amino acids to 30 amino acids, from 30 amino acids to 40 amino acids, or from 40 amino acids to 50 amino acids, such that the variant fHbp exhibits reduced affinity to human factor H (fH), compared to a reference fHbp, and where the variant fHbp elicits a bactericidal immune response to one or moreN. meningitidis strains when administered to a mammalian host. In some cases, the variant fHbp differs in amino acid sequence from a reference wild-typeN. meningitidis fHbp by no more than from 1 to 10 acid substitutions. In some cases, the variant fHbp differs in amino acid sequence from a reference wild-typeN. meningitidis fHbp by only one amino acid substitution.
In some cases, variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to a reference fHbp sequence; where the variant fHbp comprises one or more amino acid substitutions relative to the reference fHbp sequence such that the variant fHbp exhibits an affinity for human fH that is 85% or less of the binding affinity of the reference fHbp for human fH, e.g., the variant fHbp exhibits an affinity for human fH that is from about 85% to about 75%, from about 75% to about 65%, from about 65% to about 55%, from about 55% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%, of the binding affinity of the affinity of the reference fHbp for human fH; and the variant fHbp induces a bactericidal immune response to at least one strain ofN. meningitidis when administered to a mammalian host (e.g., a human; or a non-human animal model).
A variant fHbp of the present disclosure maintains substantially the same conformation of a reference (e.g., wild-type) fHbp that binds human fH when the reference fHbp is in its native conformation. Whether a variant fHbp of the present disclosure maintains substantially the same conformation of a reference (e.g., wild-type) fHbp that binds human fH can be determined using antibodies that bind wild-type fHbp when the wild-type fHbp is in its native conformation. Such antibodies include, e.g., JAR 41; JAR 4; and JAR 31. See, e.g.,Vu et al. (2012) Sci. Reports 2:341. A hybridoma producing JAR 4 monoclonal antibody has the American Type Culture Collection (ATCC) number PTA-8943; see also USPN 8,470,340. For example, in some cases, a variant fHbp of the present disclosure retains binding to JAR 4; e.g., a variant fHbp of the present disclosure retains at least 75%, at least 80%, at least 85%, at least 90%, or at least 95%, binding to JAR 4 of a reference fHbp (e.g., fHbp ID 1, fHbp ID 22, or fHbp ID 55) in its native conformation.
Variants of fHbp ID 1A "reference fHbp" from which a variant fHbp of the present disclosure is derived is in some cases fHbp ID 1. The amino acid sequence of fHbp ID 1 is set out below.
fHbp ID 1:
In some cases, a variant fHbp of the present disclosure is a variant group 1 fHbp. In some cases, a variant fHbp of the present disclosure is a variant group 1 fHbp, and is a modular group I fHbp. In some cases, variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1; where the variant fHbp comprises one or more amino acid substitutions relative to fHbp ID 1 such that the variant fHbp exhibits an affinity for human fH that is 85% or less of the binding affinity of fHbp ID 1 for human fH, e.g., the variant fHbp exhibits an affinity for human fH that is from about 85% to about 75%, from about 75% to about 65%, from about 65% to about 55%, from about 55% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%, of the binding affinity of the affinity of fHbp ID 1 for human fH; and the variant fHbp induces a bactericidal immune response to at least one strain ofN. meningitidis when administered to a mammalian host (e.g., a human; or a non-human animal model).
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution selected from at least one of: a) an amino acid substitution of the glutamine at amino acid 38 (Q38); b) an amino acid substitution of the glutamic acid at amino acid 92 (E92); c) a substitution of glycine for arginine at amino acid 130 (R130G); d) an amino acid substitution of the serine at amino acid 223 (S223); and e) a substitution of histidine for leucine at amino acid 248 (H248L), based on the numbering of fHbp ID 1.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the glutamine at amino acid 38 (Q38). In some cases, the variant fHbp comprises a Q38R substitution. Other amino acids with positively charged or aromatic side chains, such as lysine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, in some cases, the variant fHbp comprises a Q38K substitution, a Q38H substitution, a Q38F substitution, a Q38Y substitution, or a Q38W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 20 and set forth in SEQ ID NO:5.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the glutamic acid at amino acid 92 (E92). In some cases the fHbp variant comprises an E92K substitution. Other amino acids with positively charged or aromatic side chains, such as arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases the fHbp variant comprises an E92R substitution, an E92H substitution, an E92F substitution, an E92Y substitution, or an E92W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 21 and set forth in SEQ ID NO:6.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a substitution of glycine for arginine at amino acid 130 (R130G). For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 22 and set forth in SEQ ID NO:7. Other amino acids with negatively charged or aromatic side chains, such as aspartate, glutamate, phenylalanine, tyrosine, or tryptophan, may also be substituted at R130. Thus, for example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an R130D substitution, an R130E substitution, an R130F substitution, an R130Y substitution, or an R130W substitution.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the serine at amino acid 223 (S223). In some cases, the fHbp variant comprises an S223R substitution. Other amino acids with positively charged or aromatic side chains, such as lysine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises an S223K substitution, an S223H substitution, an S223F substitution, an S223Y substitution, or an S223W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 23 and set forth in SEQ ID NO:8.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a substitution of histidine for leucine at amino acid 248 (H248L). For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 24 and set forth in SEQ ID NO:9. Other amino acids with non-polar, negatively charged or aromatic side chains, such as isoleucine, valine, aspartate, glutamate, phenylalanine, tyrosine or tryptophan, also may be substituted at H248. Thus, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an H248I substitution, an H248V substitution, an H248D substitution, an H248E substitution, an H248F substitution, an H248Y substitution, or an H248W substitution.
Combinations of amino acid substitutionsIn some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution selected from two or more of: a) an amino acid substitution of the glutamine at amino acid 38 (Q38); b) an amino acid substitution of the glutamic acid at amino acid 92 (E92); c) a substitution of glycine for arginine at amino acid 130 (R130G); d) an amino acid substitution of the serine at amino acid 223 (S223); and e) a substitution of histidine for leucine at amino acid 248 (H248L), based on the numbering of fHbp ID 1.
Combinations of substitutions may be included wherein the two substitutions are in different structural domains, and each independently decreases binding of fH to fHbp (e.g., one substitution in the N-terminal domain, in combination with an amino acid substitution in the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the N-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the C-terminal domain; and a second amino acid substitution within the C-terminal domain.
For example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: a) an amino acid substitution of the glutamine at amino acid 38 (Q38) and b) an amino acid substitution of the glutamic acid at amino acid 92 (E92); or where the variant fHbp comprises: a) an amino acid substitution of the glutamine at amino acid 38 (Q38) and c) a substitution of glycine for arginine at amino acid 130 (R130G); or where the variant fHbp comprises a) an amino acid substitution of the glutamine at amino acid 38 (Q38) and d) an amino acid substitution of the serine at amino acid 223 (S223); or where the variant fHbp comprises a) an amino acid substitution of the glutamine at amino acid 38 (Q38) and e) a substitution of histidine for leucine at amino acid 248 (H248L), based on the numbering of fHbp ID 1.
As additional non-limiting examples, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: b) an amino acid substitution of the glutamic acid at amino acid 92 (E92) and c) a substitution of glycine for arginine at amino acid 130 (R130G); or where the variant fHbp comprises b) an amino acid substitution of the glutamic acid at amino acid 92 (E92) and d) an amino acid substitution of the serine at amino acid 223 (S223); or where the variant fHbp comprises b) an amino acid substitution of the glutamic acid at amino acid 92 (E92) and e) a substitution of histidine for leucine at amino acid 248 (H248L); or where the variant fHbp comprises c) a substitution of glycine for arginine at amino acid 130 (R130G) and d) an amino acid substitution of the serine at amino acid 223 (S223); or where the variant fHbp comprises c) a substitution of glycine for arginine at amino acid 130 (R130G) and e) a substitution of histidine for leucine at amino acid 248 (H248L); or where the variant fHbp comprises d) an amino acid substitution of the serine at amino acid 223 (S223) and e) a substitution of histidine for leucine at amino acid 248 (H248L), based on the numbering of fHbp ID 1.
As additional non-limiting examples, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 1 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: i) a Q38R substitution; and ii) an R130G substitution, based on the numbering of fHbp ID 1.
Also provided herein are variant fHbp proteins that include one or more substitutions relative to amino acid sequence of fHbp ID 1 as set forth above and further include the substitution R41S. Exemplary variant fHbp include a R41S substitution and a substitution at S223, e.g., R41S/S223R relative to fHbp ID 1 or a R41S substitution and a H248L substitution relative to fHbp ID 1. In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:1, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises two or more of the following amino acid substitutions: a) a substitution of serine for arginine at amino acid 41 (R41S); b) a substitution of arginine for serine at amino acid 223 (S223R); c) a substitution of leucine for histidine at amino acid 248 (H248L), based on the numbering of fHbp ID 1.
Also disclosed herein are variant fHbp proteins that include one or more substitutions relative to amino acid sequence of fHbp ID 1 as set forth above and further include the substitutions disclosed in
US2011/0256180, which is herein incorporated by reference in its entirety.
A "reference fHbp" from which a variant fHbp of the present disclosure is derived is in some cases fHbp ID 22. The amino acid sequence of fHbp ID 22 is set out below.
fHbp ID 22:
In some cases, a variant fHbp of the present disclosure is a variant group 2 fHbp. In some cases, a variant fHbp of the present disclosure is a variant group 2 fHbp, and is a modular group III fHbp. In some cases, variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2; where the variant fHbp comprises one or more amino acid substitutions relative to fHbp ID 22 such that the variant fHbp exhibits an affinity for human fH that is 85% or less of the binding affinity of fHbp ID 22 for human fH, e.g., the variant fHbp exhibits an affinity for human fH that is from about 85% to about 75%, from about 75% to about 65%, from about 65% to about 55%, from about 55% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%, of the binding affinity of the affinity of fHbp ID 22 for human fH; and the variant fHbp induces a bactericidal immune response to at least one strain ofN. meningitidis when administered to a mammalian host (e.g., a human; or a non-human animal model).
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution selected from at least one of: a) a substitution of isoleucine for asparagine at amino acid 115 (N115I); b) a substitution of glycine for aspartic acid at amino acid 121 (D121G); c) a substitution of threonine for serine at amino acid 128 (S128T); d) an amino acid substitution of the valine at position 131 (V131); e) an amino acid substitution of the lysine at position 219 (K219); f) an amino acid substitution of the glycine at position 220 (G220), relative to the amino acid sequence of fHbp ID 22. As noted herein, the numbering of the amino acid residue is based on that of fHbp ID 1.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a substitution of isoleucine for asparagine at amino acid 115 (N115I). For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 25 and set forth in SEQ ID NO:10. Other amino acids with non-polar, positively charged or aromatic side chains, such as valine, leucine, lysine, arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at N115. Thus, for example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an N115V substitution, an N115L substitution, an N115K substitution, an N115R substitution, an N115H substitution, an N115F substitution, an N115Y substitution, or an N115W substitution relative to amino acid sequence of fHbp ID 22.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a substitution of glycine for aspartic acid at amino acid 121 (D121G). For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 26 and set forth in SEQ ID NO:11. Other amino acids with non-polar, positively charged or aromatic side chains, such as leucine, isoleucine, valine, lysine, arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at D121. Thus, for example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a D121L substitution, a D121I substitution, a D121V substitution, a D121K substitution, a D121R substitution, a D121H substitution, a D121F substitution, a D121Y substitution, or a D121W substitution relative to amino acid sequence of fHbp ID 22.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises a substitution of threonine for serine at amino acid 128 (S128T). For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 27 and set forth in SEQ ID NO:12. Other amino acids with polar, charged or aromatic side chains, such as methionine, asparagine, glutamine, aspartate, glutamate, lysine, arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at S128. Thus, for example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an S128M substitution, an S128N substitution, an S128D substitution, an S128E substitution, an S128K substitution, an S128R substitution, an S128H substitution, an S128F substitution, an S128Y substitution, or an S128W substitution relative to amino acid sequence of fHbp ID 22.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the valine at position 131 (V131). In some cases, the fHbp variant comprises a V131D substitution. Other amino acids with charged or aromatic side chains, such as glutamate, lysine, arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises a V131E substitution, a V131K substitution, a V131R substitution, a V131H substitution, a V131F substitution, a V131Y substitution, or a V131W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 28 and set forth in SEQ ID NO:13 relative to amino acid sequence of fHbp ID 22.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the lysine at position 219 (K219). In some cases, the fHbp variant comprises a K219N substitution. Other amino acids with polar, negatively charged or aromatic side chains, such as glutamine, aspartate, glutamate, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises a K219Q substitution, a K219D substitution, a K219E substitution, a K219F substitution, a K219Y substitution, or a K219W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 29 and set forth in SEQ ID NO:14.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the glycine at position 220 (G220). In some cases, the fHbp variant comprises a G220S substitution. Other amino acids with polar, charged or aromatic side chains, such as asparagine, glutamine, aspartate, glutamate, lysine, arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises a G220N substitution, a G220Q substitution, a G220D substitution, a G220E substitution, a G220K substitution, a G220R substitution, a G220H substitution, a G220F substitution, a G220Y substitution, or a G220W substitution. For example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 30 and set forth in SEQ ID NO:15.
Combinations of amino acid substitutionsIn some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution selected from two or more of: a) a substitution of isoleucine for asparagine at amino acid 115 (N115I); b) a substitution of glycine for aspartic acid at amino acid 121 (D121G); c) a substitution of threonine for serine at amino acid 128 (S128T); d) an amino acid substitution of the valine at position 131 (V131); e) an amino acid substitution of the lysine at position 219 (K219); f) an amino acid substitution of the glycine at position 220 (G220), relative to amino acid sequence of fHbp ID 22. As noted herein, the numbering of the residues is based on the numbering of the amino acids in fHbp ID 1.
Combinations of substitutions may be included wherein the two substitutions are in different structural domains, and each independently decreases binding of fH to fHbp (e.g., one substitution in the N-terminal domain, in combination with an amino acid substitution in the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the N-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the C-terminal domain; and a second amino acid substitution within the C-terminal domain.
For example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: a) a substitution of isoleucine for asparagine at amino acid 115 (N115I) and b) a substitution of glycine for aspartic acid at amino acid 121 (D121G); or where the variant fHbp comprises: a) a substitution of isoleucine for asparagine at amino acid 115 (N115I) and c) a substitution of threonine for serine at amino acid 128 (S128T); or where the variant fHbp comprises: a) a substitution of isoleucine for asparagine at amino acid 115 (N1151) and d) an amino acid substitution of the valine at position 131 (V131); or where the variant fHbp comprises: a) a substitution of isoleucine for asparagine at amino acid 115 (N115I) and e) an amino acid substitution of the lysine at position 219 (K219); or where the variant fHbp comprises: a) a substitution of isoleucine for asparagine at amino acid 115 (N1151) and f) an amino acid substitution of the glycine at position 220 (G220), relative to amino acid sequence of fHbp ID 22, the numbering of the substituted residue based on the numbering of amino acid sequence of fHbp ID 1.
As additional non-limiting examples, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: b) a substitution of glycine for aspartic acid at amino acid 121 (D121G) and c) a substitution of threonine for serine at amino acid 128 (S128T); or where the variant fHbp comprises: b) a substitution of glycine for aspartic acid at amino acid 121 (D121G) and d) an amino acid substitution of the valine at position 131 (V131); or where the variant fHbp comprises: b) a substitution of glycine for aspartic acid at amino acid 121 (D121G) and e) an amino acid substitution of the lysine at position 219 (K219); or where the variant fHbp comprises: b) a substitution of glycine for aspartic acid at amino acid 121 (D121G) and f) an amino acid substitution of the glycine at position 220 (G220), relative to amino acid sequence of fHbp ID 22. The numbering of the substituted residue(s) is based on the numbering of amino acid sequence of fHbp ID 1.
As additional non-limiting examples, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: c) a substitution of threonine for serine at amino acid 128 (S128T) and d) an amino acid substitution of the valine at position 131 (V131); or where the variant fHbp comprises: c) a substitution of threonine for serine at amino acid 128 (S128T) and e) an amino acid substitution of the lysine at position 219 (K219); or where the variant fHbp comprises: c) a substitution of threonine for serine at amino acid 128 (S128T) and f) an amino acid substitution of the glycine at position 220 (G220); or where the variant fHbp comprises: d) an amino acid substitution of the valine at position 131 (V131) and e) an amino acid substitution of the lysine at position 219 (K219); or where the variant fHbp comprises: d) an amino acid substitution of the valine at position 131 (V131) and f) an amino acid substitution of the glycine at position 220 (G220); or where the variant fHbp comprises: e) an amino acid substitution of the lysine at position 219 (K219) and f) an amino acid substitution of the glycine at position 220 (G220), ), relative to amino acid sequence of fHbp ID 22. The numbering of the substituted residue(s) is based on the numbering of amino acid sequence of fHbp ID 1.
Combinations of substitutions may be included wherein the two substitutions are in different structural domains, and each independently decreases binding of fH to fHbp (e.g. one from the N-terminal domain (e.g., N115I, D121G, S128T or V131D) in combination with one from the C-terminal domain (e.g., D211A, K219N, G220S).
For example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: i) an N115I substitution; and ii) a D211A substitution.
As another example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: i) an N1151 substitution; and ii) a K219N substitution.
As another example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:2, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 22 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: i) an N1151 substitution; and ii) a G220S substitution.
Also disclosed herein are variant fHbp polypeptides that have increased thermal stability compared to wild type fHbp ID22. In some cases, the variant fHbp may include the substitutions L130R and G133D relative to fHbp ID 22 (SEQ ID NO:2), wherein the variant fHbp comprises an amino acid sequence having greater than 85% amino acid sequence identity to SEQ ID NO:2, wherein the variant fHbp binds human factor H (fH) with an affinity that is 50% or less of the affinity of fHbp ID 22 for human fH, wherein the variant induces a bactericidal antibody response in a mammalian host, and the variant has a higher thermal stability that WT fHbp ID 22. The thermal stability of the variant fHbp may be higher than a WT fHbp (e.g., fHbp ID 22) by at least 5°C, 10°C , 15°C, 20°C, or more, e.g., higher by 5°C-30°C, 5°C-25°C, 5°C-20°C, 10°C-20°C, or 15°C-20°C. As used herein, "thermal stability" refers to stability of a protein when exposed to higher temperature; a thermal stability variant protein maintains its conformation at a higher temperature than a wild type protein. For example, the variant fHbp, that include the double mutation that increases thermal stability compared to thermal stability of wild type (WT) fHbp, e.g., WT fHbp ID 22, may unfold at a higher temperature compared to WT fHbp. In certain cases, the N-terminal domain of the variant fHbp may unfold at a higher temperature than the N-terminal domain of the WT fHbp (e.g., fHbp ID 22).
In certain embodiments, a variant of factor H binding protein (fHbp) is disclosed, wherein the variant comprises amino acid substitutions L130R and G133D and at least one of the substitutions: R80A, N115I, D121G, S128T, V131, D211A, E218A, K219 (e.g., K219N), G220 (e.g., G220S), E248A, G236I, T221A, and H223A relative to fHbp ID 22 (SEQ ID NO:2), wherein the variant comprises an amino acid sequence having greater than 85% amino acid sequence identity to SEQ ID NO:2, wherein the variant fHbp binds human factor H (fH) with an affinity that is 50% or less of the affinity of fHbp ID 22 for human fH, and wherein the variant induces a bactericidal antibody response in a mammalian host.
In some cases, the variant fHbp may include a combination of substitutions, such as, L130R, G133D, and at least one amino acid substitution selected from: a) N115I; b) D121G; c) S128T; d) V131D; e) K219 (e.g., K219N); and f) G220 (e.g., G220S), wherein the amino acid substitutions are relative to fHbp ID 22 (SEQ ID NO:2), wherein the variant fHbp comprises an amino acid sequence having greater than 85% amino acid sequence identity to SEQ ID NO:2, wherein the variant fHbp binds human factor H (fH) with an affinity that is 50% or less of the affinity of fHbp ID 22 for human fH, and wherein the variant induces a bactericidal antibody response in a mammalian host.
In certain embodiments, a variant of factor H binding protein (fHbp) is disclosed, wherein the variant comprises amino acid substitutions L130R and G133D and at least one of the substitutions: R80A, D211A, E218A, E248A, G236I, T221A, and H223A relative to fHbp ID 22 (SEQ ID NO:2), wherein the variant comprises an amino acid sequence having greater than 85% amino acid sequence identity to SEQ ID NO:2, wherein the variant fHbp binds human factor H (fH) with an affinity that is 50% or less of the affinity of fHbp ID 22 for human fH, and wherein the variant induces a bactericidal antibody response in a mammalian host.
Exemplary variant fHbp include a polypeptide having an amino acid sequence having greater than 85% amino acid sequence identity (e.g., at least 90% identity, at least 95%, at least 96% identity, at least 97% identity, at least 98% identity, at least 99% identity to SEQ ID NO:2, and including the following substitutions relative to the amino acid sequence of SEQ ID NO:2:L130R and G133D; L130R, G133D, and K219N; or L130R, G133D, and G220S.
Also disclosed herein are variant fHbp proteins that include one or more substitutions relative to amino acid sequence of fHbp ID 22 as set forth above and further include the substitutions disclosed in
US2011/0256180, which is herein incorporated by reference in its entirety.
A "reference fHbp" from which a variant fHbp of the present disclosure is derived is in some cases fHbp ID 55. The amino acid sequence of fHbp ID 55 is set out below.
fHbp ID 55:
In some cases, a variant fHbp of the present disclosure is a variant group 1 fHbp. In some cases, a variant fHbp of the present disclosure is a variant group 1 fHbp, and is a modular group IV fHbp.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3; where the variant fHbp comprises one or more amino acid substitutions relative to fHbp ID 55 such that the variant fHbp exhibits an affinity for human fH that is 85% or less of the binding affinity of fHbp ID 55 for human fH, e.g., the variant fHbp exhibits an affinity for human fH that is from about 85% to about 75%, from about 75% to about 65%, from about 65% to about 55%, from about 55% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%, of the binding affinity of the affinity of fHbp ID 55 for human fH; and the variant fHbp induces a bactericidal immune response to at least one strain ofN. meningitidis when administered to a mammalian host (e.g., a human; or a non-human animal model).
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution selected from at least one of: a) an amino acid substitution of the glutamic acid at position 92 (E92); b) an amino acid substitution of the serine at position 223 (S223); and c) an amino acid substitution of the histidine at position 248 (H248), relative to the amino acid sequence of fHbp ID 55, where the numbering of the amino acid residues is based on the numbering of fHbp ID 1.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the glutamic acid at position 92 (E92). In some cases, the fHbp variant comprises an E92K substitution. Other amino acids with positively charged or aromatic side chains, such as arginine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises an E92R substitution, an E92H substitution, an E92F substitution, an E92Y substitution, or an E92W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 31 and set forth in SEQ ID NO:16.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the serine at position 223 (S223). In some cases, the fHbp variant comprises an S223R substitution. Other amino acids with positively charged or aromatic side chains, such as lysine, histidine, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises an S223K substitution, an S223H substitution, an S223F substitution, an S223Y substitution, or an S223W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 32 and set forth in SEQ ID NO:17.
In some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises an amino acid substitution of the histidine at position 248 (H248). In some cases, the fHbp variant comprises an H248L substitution. Other amino acids with non-polar, negatively charged or aromatic side chains, such as isoleucine, valine, aspartate, glutamate, phenylalanine, tyrosine or tryptophan, also may be substituted at this position. Thus, for example, in some cases, the fHbp variant comprises an H248I substitution, an H248V substitution, an H248D substitution, an H248E substitution, an H248F substitution, an H248Y substitution, or an H248W substitution. As one example, a variant fHbp of the present disclosure can comprise the amino acid sequence depicted inFigure 33 and set forth in SEQ ID NO:18.
Combinations of amino acid substitutionsIn some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises two or more amino acid substitutions selected from the group consisting of: a) an amino acid substitution of the glutamic acid at position 92 (E92); b) an amino acid substitution of the serine at position 223 (S223); and c) an amino acid substitution of the histidine at position 248 (H248), relative to fHbp ID 55, where the numbering of the residue is based on the numbering of amino acids in the sequence for fHbp ID 1.
Combinations of substitutions may be included wherein the two substitutions are in different structural domains, and each independently decreases binding of fH to fHbp (e.g., one substitution in the N-terminal domain, in combination with an amino acid substitution in the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the C-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the N-terminal domain; and a second amino acid substitution within the N-terminal domain. In some cases, a variant fHbp of the present disclosure comprises a first amino acid substitution within the C-terminal domain; and a second amino acid substitution within the C-terminal domain.
For example, in some cases, a variant fHbp of the present disclosure comprises an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99%, amino acid sequence identity to SEQ ID NO:3, where the variant fHbp binds human fH with an affinity that 50% or less (e.g., from about 50% to about 45%, from about 45% to about 35%, from about 35% to about 25%, from about 25% to about 15%, from about 15% to about 10%, from about 10% to about 5%, from about 5% to about 2%, from about 2% to about 1%, or from about 1% to about 0.1%, or less than 0.1%) of the affinity of fHbp ID 55 for human fH, where the variant induces a bactericidal antibody response to at least one strain ofN. meningitidis in a mammalian host, and where the variant fHbp comprises: a) an amino acid substitution of the glutamic acid at position 92 (E92) and b) an amino acid substitution of the serine at position 223 (S223); or where the variant fHbp comprises: a) an amino acid substitution of the glutamic acid at position 92 (E92) and c) an amino acid substitution of the histidine at position 248 (H248); or where the variant fHbp comprises: b) an amino acid substitution of the serine at position 223 (S223) and c) an amino acid substitution of the histidine at position 248 (H248); or where the variant fHbp comprises: a) an amino acid substitution of the glutamic acid at position 92 (E92) and b) an amino acid substitution of the serine at position 223 (S223) and c) an amino acid substitution of the histidine at position 248 (H248), relative to fHbp ID 55, where the numbering of the residue is based on the numbering of amino acids in the sequence for fHbp ID 1.
Also disclosed herein are variant fHbp proteins that include one or more substitutions relative to amino acid sequence of fHbp ID 55 as set forth above and further include the substitutions disclosed in
US2011/0256180, which is herein incorporated by reference in its entirety.
A variant fHbp of the present disclosure can be a fusion polypeptide, e.g., a polypeptide comprising a variant fHbp as described above, and a heterologous polypeptide (e.g., a fusion partner). The fusion partner can be at the N-terminus of the variant fHbp, at the C-terminus of the variant fHbp, or at an internal site within the fHbp.
Suitable fusion partners include peptides and polypeptides that confer enhanced stabilityin vivo (e.g., enhanced serum half-life); provide ease of purification, e.g., (His)n, e.g., 6His, and the like; provide for secretion of the fusion protein from a cell; provide an epitope tag, e.g., GST, hemagglutinin (HA; e.g., YPYDVPDYA; SEQ ID NO:26), FLAG (e.g., DYKDDDDK; SEQ ID NO:27), c-myc (e.g., EQKLISEEDL; SEQ ID NO:28), and the like; provide a detectable signal, e.g., an enzyme that generates a detectable product (e.g., β-galactosidase, luciferase), or a protein that is itself detectable, e.g., a green fluorescent protein, a yellow fluorescent protein, etc.; provides for multimerization, e.g., a multimerization domain such as an Fc portion of an immunoglobulin; and the like.
METHODS OF PRODUCTIONThe fHbps of the present disclosure can be produced by any suitable method, including recombinant and non-recombinant methods (e.g., chemical synthesis). Where the subject fHbp is produced using recombinant techniques, the methods can involve any suitable construct and any suitable host cell, which can be a prokaryotic or eukaryotic cell, usually a bacterial or yeast host cell, more usually a bacterial cell. Methods for introduction of genetic material into host cells include, for example, transformation, electroporation, conjugation, calcium phosphate methods and the like. The method for transfer can be selected so as to provide for stable expression of the introduced fHbp-encoding nucleic acid. The fHbp-encoding nucleic acid can be provided as an inheritable episomal element (e.g., plasmid) or can be genomically integrated.
The present disclosure provides nucleic acids (including isolated nucleic acids) that comprise a nucleotide sequence encoding a fHbp variant of the present disclosure. In some embodiments, the nucleotide sequence encoding the fHbp variant is operably linked to a transcriptional control element, e.g., a promoter. The promoter is in some cases constitutive. The promoter is in some cases inducible. In some cases, the promoter is suitable for use (e.g., active in) a prokaryotic host cell. In some cases, the promoter is suitable for use (e.g., active in) a eukaryotic host cell.
In some instances, a nucleic acid comprising a nucleotide sequence encoding a fHbp variant of the present disclosure is present in an expression vector. The present disclosure provides a recombinant expression vector (e.g., an isolated recombinant expression vector) that comprises a nucleotide sequence encoding a fHbp variant of the present disclosure In some embodiments, the nucleotide sequence encoding the fHbp variant is operably linked to a transcriptional control element, e.g., a promoter. The promoter is in some cases constitutive. The promoter is in some cases inducible. In some cases, the promoter is suitable for use (e.g., active in) a prokaryotic host cell. In some cases, the promoter is suitable for use (e.g., active in) a eukaryotic host cell.
Suitable vectors for transferring fHbp-encoding nucleic acid can vary in composition. Integrative vectors can be conditionally replicative or suicide plasmids, bacteriophages, and the like. The constructs can include various elements, including for example, promoters, selectable genetic markers (e.g., genes conferring resistance to antibiotics (for instance kanamycin, erythromycin, chloramphenicol, or gentamycin)), origin of replication (to promote replication in a host cell, e.g., a bacterial host cell), and the like. The choice of vector will depend upon a variety of factors such as the type of cell in which propagation is desired and the purpose of propagation. Certain vectors are useful for amplifying and making large amounts of the desired DNA sequence. Other vectors are suitable for expression in cells in culture. Still other vectors are suitable for transfer and expression in cells in a whole animal. The choice of appropriate vector is well within the skill of the art. Many such vectors are available commercially.
In one example, the vector is an expression vector based on episomal plasmids containing selectable drug resistance markers and elements that provide for autonomous replication in different host cells (e.g., in bothE. coli andN. meningitidis). One example of such a "shuttle vector" is the plasmid pFP10 (Pagotto et al. (2000) Gene 244:13-19).
Constructs (recombinant vectors) can be prepared by, for example, inserting a polynucleotide of interest into a construct backbone, typically by means of DNA ligase attachment to a cleaved restriction enzyme site in the vector. Alternatively, the desired nucleotide sequence can be inserted by homologous recombination or site-specific recombination. Typically homologous recombination is accomplished by attaching regions of homology to the vector on the flanks of the desired nucleotide sequence, while site-specific recombination can be accomplished through use of sequences that facilitate site-specific recombination (e.g., cre-lox, att sites, etc.). Nucleic acid containing such sequences can be added by, for example, ligation of oligonucleotides, or by polymerase chain reaction using primers comprising both the region of homology and a portion of the desired nucleotide sequence.
Vectors can provide for extrachromosomal maintenance in a host cell or can provide for integration into the host cell genome. Vectors are amply described in numerous publications well known to those in the art, including, e.g.,Short Protocols in Molecular Biology, (1999) F. Ausubel, et al., eds., Wiley & Sons. Vectors may provide for expression of the nucleic acids encoding the subject fHbp, may provide for propagating the subject nucleic acids, or both.
Examples of vectors that may be used include but are not limited to those derived from recombinant bacteriophage DNA, plasmid DNA or cosmid DNA. For example, plasmid vectors such as pBR322, pUC 19/18, pUC 118, 119 and the M13 mp series of vectors may be used. pET21 is also an expression vector that may be used. Bacteriophage vectors may include λgt10, λgt11, λgt18-23, λZAP/R and the EMBL series of bacteriophage vectors. Further vectors that may be utilized include, but are not limited to, pJB8, pCV 103, pCV 107, pCV 108, pTM, pMCS, pNNL, pHSG274, COS202, COS203, pWE15, pWE16 and the charomid 9 series of vectors.
For expression of a subject fHbp, an expression cassette may be employed. Thus, the present disclosure provides a recombinant expression vector comprising a subject nucleic acid. The expression vector provides transcriptional and translational regulatory sequences, and may provide for inducible or constitutive expression, where the coding region is operably linked under the transcriptional control of the transcriptional initiation region, and a transcriptional and translational termination region. These control regions may be native to an fHbp from which the subject fHbp is derived, or may be derived from exogenous sources. In general, the transcriptional and translational regulatory sequences may include, but are not limited to, promoter sequences, ribosomal binding sites, transcriptional start and stop sequences, translational start and stop sequences, and enhancer or activator sequences. Promoters can be either constitutive or inducible, and can be a strong constitutive promoter (e.g., T7, and the like).
Expression vectors generally have convenient restriction sites located near the promoter sequence to provide for the insertion of nucleic acid sequences encoding proteins of interest. A selectable marker operative in the expression host may be present to facilitate selection of cells containing the vector. In addition, the expression construct may include additional elements. For example, the expression vector may have one or two replication systems, thus allowing it to be maintained in organisms, for example in mammalian or insect cells for expression and in a prokaryotic host for cloning and amplification. In addition the expression construct may contain a selectable marker gene to allow the selection of transformed host cells. Selection genes are well known in the art and will vary with the host cell used.
It should be noted that fHbps of the present disclosure may comprise additional elements, such as a detectable label, e.g., a radioactive label, a fluorescent label, a biotin label, an immunologically detectable label (e.g., a hemagglutinin tag, a poly-Histidine tag) and the like. Additional elements of fHbp can be provided to facilitate isolation (e.g., biotin tag, immunologically detectable tag) through various methods (e.g., affinity capture, etc.). The subject fHbp can optionally be immobilized on a support through covalent or non-covalent attachment.
Isolation and purification of fHbp can be accomplished according to methods known in the art. For example, fHbp can be isolated from a lysate of cells genetically modified to express a fHbp, or from a synthetic reaction mix, by immunoaffinity purification, which generally involves contacting the sample with an anti-fHbp antibody (e.g., an anti-fHbp monoclonal antibody (mAb), such as a JAR 4 MAb or other appropriate JAR MAb known in the art), washing to remove non-specifically bound material, and eluting specifically bound fHbp. Isolated fHbp can be further purified by dialysis and other methods normally employed in protein purification methods. In one example, the fHbp can be isolated using metal chelate chromatography methods.
Host cellsAny of a number of suitable host cells can be used in the production of fHbp. In general, the fHbp described herein may be expressed in prokaryotes or eukaryotes, e.g., bacteria such asEscherichia coli or Neisseria (e.g.,N. meningitidis) in accordance with conventional techniques. Thus, the present disclosure further provides a genetically modifiedin vitro host cell, which contains a nucleic acid encoding a subject fHbp. Host cells for production (including large scale production) of a subject fHbp can be selected from any of a variety of available host cells. Examples of host cells for expression include those of a prokaryotic or eukaryotic unicellular organism, such as bacteria (e.g.,Escherichia coli strains), yeast (e.g.,Saccharomyces cerevisiae, Pichia spp., and the like), and may include host cells originally derived from a higher organism such as insects, vertebrates, e.g., mammals. Suitable mammalian cell lines include, but are not limited to, HeLa cells (e.g., American Type Culture Collection (ATCC) No. CCL-2), CHO cells (e.g., ATCC Nos. CRL9618, CCL61, CRL9096), 293 cells (e.g., ATCC No. CRL-1573), Vero cells, NIH 3T3 cells (e.g., ATCC No. CRL-1658), Huh-7 cells, BHK cells (e.g., ATCC No. CCL10), PC12 cells (ATCC No. CRL1721), COS cells, COS-7 cells (ATCC No. CRL1651), RAT1 cells, mouse L cells (ATCC No. CCLI.3), human embryonic kidney (HEK) cells (ATCC No. CRL1573), HLHepG2 cells, and the like.). In some cases, bacterial host cells and yeast host cells are of particular interest for subject fHbp production.
Subject fHbps can be prepared in substantially pure or substantially isolated form (i.e., substantially free from other Neisserial or host cell polypeptides) or substantially isolated form. The subject fHbp can be present in a composition that is enriched for the polypeptide relative to other components that may be present (e.g., other polypeptides or other host cell components). Purified subject fHbp can be provided such that the polypeptide is present in a composition that is substantially free of other expressed polypeptides, e.g., less than 90%, usually less than 60% and more usually less than 50% of the composition is made up of other expressed polypeptides.
Host cells for vesicle productionWhere a subject fHbp is to be provided in a membrane vesicle (as discussed in more detail below), a Neisserial host cell is genetically modified to express a subject fHbp. Any of a variety of Neisseria spp. strains can be modified to produce a subject fHbp, and, optionally, which produce or can be modified to produce other antigens of interest, such as PorA, can be used in the methods disclosed herein.
Methods and vectors to provide for genetic modification of Neisserial strains and expression of a desired polypeptide are known in the art. Examples of vectors and methods can be found in
WO 02/09746 and
O'Dwyer et al. (2004) Infect Immun 72:6511-80. Strong promoters, particularly constitutive strong promoters are of particular interest. Examples of promoters include the promoters of porA, porB, lbpB, tbpB, p110, hpuAB, lgtF, opa, p110, lst, hpuAB, and rmp.
Pathogenic Neisseria spp. or strains derived from pathogenic Neisseria spp., particularly strains pathogenic for humans or derived from strains pathogenic or commensal for humans, are of particular interest for use in membrane vesicle production. Examples of Neisserial spp. includeN. meningitidis, N. flavescens, N. gonorrhoeae, N. lactamica, N. polysaccharea, N. cinerea, N. mucosa, N. subflava, N. sicca, N. elongata, and the like.
N. meningitidis strains are of particular interest for genetic modification to express the subject fHbps and for use in vesicle production. The strain used for vesicle production can be selected according to a number of different characteristics that may be desired. For example, the strain may be selected according to: a desired PorA type (a "serosubtype"), capsular group, serotype, and the like; decreased capsular polysaccharide production; and the like. For example, the production strain can produce any desired PorA polypeptide, and may express one or more PorA polypeptides (either naturally or due to genetic engineering). Examples of strains include those that produce a PorA polypeptide which confers a serosubtype of P1.7,16; P1.19,15; P1.7,1; P1.5,2; P1.22a,14; P1.14 ; P1.5,10; P1.7,4; P1.12,13; as well as variants of such PorA polypeptides which may or may not retain reactivity with conventional serologic reagents used in serosubtyping. Also of interest are PorA polypeptides characterized according to PorA variable region (VR) typing (see, e.g.,Russell et al. (2004) Emerging Infect Dis 10:674-678;Sacchi CT et al. (1998) Clin Diagn Lab Immunol 5:845-55;Sacchi et al (2000) J. Infect Dis 182:1169-1176). A substantial number of distinct VR types have been identified, which can be classified into VR1 and VR2 family "prototypes". A web-accessible database describing this nomenclature and its relationship to previous typing schemes is found at neisseria.org/nm/typing/pora. Alignments of certain PorA VR1 and VR2 types are provided inRussell et al. (2004) Emerging Infect Dis 10:674-678.
Alternatively or in addition, the production strain can be a capsule deficient strain. Capsule deficient strains can provide vesicle-based vaccines that provide for a reduced risk of eliciting a significant autoantibody response in a subject to whom the vaccine is administered (e.g., due to production of antibodies that cross-react with sialic acid on host cell surfaces). "Capsule deficient" or "deficient in capsular polysaccharide" as used herein refers to a level of capsular polysaccharide on the bacterial surface that is lower than that of a naturally-occurring strain or, where the strain is genetically modified, is lower than that of a parental strain from which the capsule deficient strain is derived. A capsule deficient strain includes strains that are decreased in surface capsular polysaccharide production by at least 10%, 20%, 25%, 30%, 40%, 50%, 60%, 75%, 80%, 85%, 90% or more, and includes strains in which capsular polysaccharide is not detectable on the bacterial surface (e.g., by whole cell enzyme-linked immunosorbent assay (ELISA) using an anti-capsular polysaccharide antibody).
Capsule deficient strains include those that are capsule deficient due to a naturally-occurring or recombinantly-generated genetic modification. Naturally-occurring capsule deficient strains (see, e.g.,Dolan-Livengood et al. (2003) J. Infect. Dis. 187:1616-28), as well as methods of identifying and/or generating capsule-deficient strains (see, e.g.,Fisseha et al. (2005) Infect. Immun. 73:4070-4080;Stephens et al. (1991) Infect Immun 59:4097-102; Frosch et al. (1990) Mol Microbiol.4:1215-1218) are known in the art.
Modification of a Neisserial host cell to provide for decreased production of capsular polysaccharide may include modification of one or more genes involved in capsule synthesis, where the modification provides for, for example, decreased levels of capsular polysaccharide relative to a parent cell prior to modification. Such genetic modifications can include changes in nucleotide and/or amino acid sequences in one or more capsule biosynthesis genes rendering the strain capsule deficient (e.g., due to one or more insertions, deletions, substitutions, and the like in one or more capsule biosynthesis genes). Capsule deficient strains can lack or be non-functional for one or more capsule genes.
Of particular interest are strains that are deficient in sialic acid biosynthesis. Such strains can provide for production of vesicles that have reduced risk of eliciting anti-sialic acid antibodies that cross-react with human sialic acid antigens, and can further provide for improved manufacturing safety. Strains having a defect in sialic acid biosynthesis (due to either a naturally occurring modification or an engineered modification) can be defective in any of a number of different genes in the sialic acid biosynthetic pathway. Of particular interest are strains that are defective in a gene product encoded by the N-acetylglucosamine-6-phosphate 2-epimerase gene (known as synX AAF40537.1 or siaA AAA20475), with strains having this gene inactivated being of especial interest. For example, in one embodiment, a capsule deficient strain is generated by disrupting production of a functional synX gene product (see, e.g.,Swartley et al. (1994) J Bacteriol. 176:1530-4).
Capsule-deficient strains can also be generated from naturally-occurring strains using non-recombinant techniques, e.g., by use of bactericidal anti-capsular antibodies to select for strains with reduced levels of capsular polysaccharide.
Where the disclosure involves use of two or more strains (e.g., to produce antigenic compositions containing a subject fHbp-presenting vesicles from different strains), the strains can be selected so as to differ in one or more strain characteristics, e.g., to provide for vesicles that differ in the subject fHbp used, PorA, and the like.
Preparation of VesiclesThe antigenic compositions contemplated by the present disclosure generally include vesicles prepared from Neisserial cells that express a subject fHbp. As referred to herein "vesicles" is meant to encompass outer membrane vesicles as well as microvesicles (which are also referred to as blebs).
The antigenic composition can contain outer membrane vesicles (OMV) prepared from the outer membrane of a cultured strain ofNeisseria meningitidis spp. genetically modified to express a subject fHbp. OMVs may be obtained fromNeisseria meningitidis grown in broth or solid medium culture, preferably by separating the bacterial cells from the culture medium (e.g. by filtration or by a low-speed centrifugation that pellets the cells, or the like), lysing the cells (e.g. by addition of detergent, osmotic shock, sonication, cavitation, homogenization, or the like) and separating an outer membrane fraction from cytoplasmic molecules (e.g. by filtration; or by differential precipitation or aggregation of outer membranes and/or outer membrane vesicles, or by affinity separation methods using ligands that specifically recognize outer membrane molecules; or by a high-speed centrifugation that pellets outer membranes and/or outer membrane vesicles, or the like); outer membrane fractions may be used to produce OMVs.
The antigenic composition can contain microvesicles (MV) (or "blebs") containing subject fHbps, where the MV or blebs are released during culture of a
Neisseria meningitidis strain genetically modified to express a subject fHbp. For example, MVs may be obtained by culturing a strain of
Neisseria meningitidis in broth culture medium, separating whole cells from the broth culture medium (e.g. by filtration, or by a low-speed centrifugation that pellets only the cells and not the smaller blebs, or the like), and then collecting the MVs that are present in the cell-free culture medium (e.g. by filtration, differential precipitation or aggregation of MVs, or by a high-speed centrifugation that pellets the blebs, or the like). Strains for use in production of MVs can generally be selected on the basis of the amount of blebs produced in culture (e.g., bacteria can be cultured in a reasonable number to provide for production of blebs suitable for isolation and administration in the methods described herein). An exemplary strain that produces high levels of blebs is described in
PCT Publication No. WO 01/34642. In addition to bleb production, strains for use in MV production may also be selected on the basis of NspA production, where strains that produce higher levels of NspA may be of particular interest (for examples of
N. meningitidis strains having different NspA production levels, see, e.g.,
Moe et al. (1999 Infect. Immun. 67: 5664). Other strains of interest for use in production of blebs include strains having an inactivated GNA33 gene, which encodes a lipoprotein required for cell separation, membrane architecture and virulence (see, e.g.,
Adu-Bobie et al. (2004) Infect Immun.72:1914-1919).
The antigenic compositions of the present disclosure can contain vesicles from one strain, or from 2, 3, 4, 5 or more strains, which strains may be homologous or heterologous, usually heterologous, to one another. For example, the strains may be homologous or heterologous with respect to PorA and/or the fHbp from which the subject fHbp is derived. The vesicles can be prepared from strains that express more than one subject fHbp (e.g., 1, 2, 3, or more subject fHbp) which may be composed of fHbp amino acid sequences from different variants (v.1, v.2, or v.3) or subvariants (e.g., a subvariant of v.1, v.2, or v.3).
The antigenic compositions can comprise a mixture of OMVs and MVs presenting the same or different subject fHbps, where the subject fHbps may optionally present epitopes from different combinations of fHbp variants and/or subvariants and where the OMVs and/or MVs may be from the same or different strains. Vesicles from different strains can be administered as a mixture, or can be administered serially.
Where desired (e.g., where the strains used to produce vesicles are associated with endotoxin or particular high levels of endotoxin), the vesicles are optionally treated to reduce endotoxin, e.g., to reduce toxicity following administration. Although less desirable as discussed below, reduction of endotoxin can be accomplished by extraction with a suitable detergent (for example, BRIJ-96, sodium deoxycholate, sodium lauroylsarcosinate, Empigen BB, Triton X-100, non-ionic detergent TWEEN 20 (sorbitan monolaurate polyoxyethylene), non-ionic detergent TWEEN 80, at a concentration of 0.1-10%, e.g., 0.5-2%, and sodium dodecyl sulfate (SDS)). Where detergent extraction is used, it is preferable to use a detergent other than deoxycholate.
The vesicles of the antigenic compositions can be prepared without detergent, e.g., without use of deoxycholate. Although detergent treatment is useful to remove endotoxin activity, it may deplete the native fHbp lipoprotein and/or subject fHbp (including lipidated fHbp) by extraction during vesicle production. Thus it may be particularly desirable to decrease endotoxin activity using technology that does not require a detergent. In one approach, strains that are relatively low producers of endotoxin (lipopolysaccharide, LPS) are used so as to avoid the need to remove endotoxin from the final preparation prior to use in humans. For example, the vesicles can be prepared from Neisseria mutants in which lipooligosaccharide or other antigens that may be undesirable in a vaccine (e.g. Rmp) is reduced or eliminated.
Vesicles can be prepared from
N. meningitidis strains that contain genetic modifications that result in decreased or no detectable toxic activity of lipid A. For example, such strain can be genetically modified in lipid A biosynthesis (
Steeghs et al. (1999) Infect Immun 67:4988-93;
van der Ley et al. (2001) Infect Immun 69:5981-90;
Steeghs et al. (2004) J Endotoxin Res 10:113-9;
Fissha et al, (2005) Infect Immun 73:4070). The immunogenic compositions may be detoxified by modification of LPS, such as downregulation and/or inactivation of the enzymes encoded by lpxL1 or lpxL2, respectively. Production of a penta-acylated lipid A made in lpxL1 mutants indicates that the enzyme encoded by lpxL1 adds the C12 to the N-linked 3-OH C14 at the 2' position of GlcN II. The major lipid A species found in lpxL2 mutants is tetra-acylated, indicating the enzyme encoded by lpxL2 adds the other C12, i.e., to the N-linked 3-OH C14 at the 2 position of GlcN I. Mutations resulting in a decreased (or no) expression of these genes (or decreased or no activity of the products of these genes) result in altered toxic activity of lipid A (
van der Ley et al. (2001) Infect Immun 69:5981-90). Tetra-acylated (lpxL2 mutant) and penta acylated (lpxL1 mutant) lipid A are less toxic than the wild-type lipid A. Mutations in the lipid A 4'-kinase encoding gene (lpxK) also decrease the toxic activity of lipid A. Of particular interest for use in production of vesicles (e.g., MV or OMV) are
N. meningitidis strains genetically modified so as to provide for decreased or no detectable functional LpxL1-encoded protein, e.g., where the Neisseria bacterium (e.g.,
N. meningitidis strain) is genetically modified to provide for decreased or no activity of a gene product of the lpxL1 gene. For example, the Neisseria bacterium can be genetically modified to have an lpxL1 gene knockout, e.g., where the lpxL1 gene is disrupted. See, e.g.,
US Patent Publication No. 2009/0035328. The Neisseria bacterium can be genetically modified to provide for decreased or no activity of a gene product of the lpxL2 gene. The Neisseria bacterium can be genetically modified to provide for decreased or no activity of a gene product of the lpxL1 gene and the lpxL2 gene. Such vesicles provide for reduced toxicity as compared to
N. meningitidis strains that are wild-type for LPS production, while retaining immunogenicity of subject fHbp.
LPS toxic activity can also be altered by introducing mutations in genes/loci involved in polymyxin B resistance (such resistance has been correlated with addition of aminoarabinose on the 4' phosphate of lipid A). These genes/loci could be pmrE that encodes a UDP-glucose dehydrogenase, or a region of antimicrobial peptide-resistance genes common to many enterobacteriaciae which could be involved in aminoarabinose synthesis and transfer. The gene pmrF that is present in this region encodes a dolicol-phosphate manosyl transferase (Gunn J. S., Kheng, B. L., Krueger J., Kim K., Guo L., Hackett M., Miller S. I. 1998. Mol. Microbiol. 27: 1171-1182).
Mutations in the PhoP-PhoQ regulatory system, which is a phospho-relay two component regulatory system (e.g., PhoP constitutive phenotype, PhoPc), or low Mg++ environmental or culture conditions (that activate the PhoP-PhoQ regulatory system) lead to the addition of aminoarabinose on the 4'-phosphate and 2-hydroxymyristate replacing myristate (hydroxylation of myristate). This modified lipid A displays reduced ability to stimulate E-selectin expression by human endothelial cells and TNF secretion from human monocytes.
Polymyxin B resistant strains are also suitable for use, as such strains have been shown to have reduced LPS toxicity (see, e.g.,van der Ley et al. (1994) In: Proceedings of the ninth international pathogenic Neisseria conference. The Guildhall, Winchester, England). Alternatively, synthetic peptides that mimic the binding activity of polymyxin B may be added to the antigenic compositions to reduce LPS toxic activity (see, e.g.,Rustici et al. (1993) Science 259:361-365;Porro et al. (1998) Prog Clin Biol Res.397:315-25).
Endotoxin can also be reduced through selection of culture conditions. For example, culturing the strain in a growth medium containing 0.1 mg-100 mg of aminoarabinose per liter medium provides for reduced lipid toxicity (see, e.g.,
WO 02/097646).
"Compositions", "antigen composition", "antigenic composition" or "immunogenic composition" is used herein as a matter of convenience to refer generically to compositions comprising a subject fHbp as disclosed herein, which subject fHbp may be optionally conjugated to further enhance immunogenicity. Compositions useful for eliciting antibodies, e.g., antibodies againstNeisseria meningitidis, e.g., bactericidal antibodies toNeisseria meningitidis, in a human are specifically contemplated by the present disclosure. Antigenic compositions can contain 1, 2, or more different subject fHbps. Where there is more than one type of fHbp, each subject fHbps may present epitopes from different combinations of fHbp variants and/or subvariants.
Antigenic compositions contain an immunologically effective amount of a subject fHbp, and may further include other compatible components, as needed. Compositions of the present disclosure can contain fHbp that are low fH binders. The composition contain one or more fHbp, in which at least one fHbp is a low fH binder. Where there is more than one fHbp in a composition, each fHbp may be different (e.g. in amino acid sequences and/or conjugation).
In some cases, an antigenic composition of the present disclosure comprises only one fHbp variant of the present disclosure. In some cases, an antigenic composition of the present disclosure comprises two or more different fHbp variants of the present disclosure. As non-limiting examples, in some cases, an antigenic composition of the present disclosure comprises:
- 1) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 2) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at R130 (e.g., R130G);
- 3) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at S223 (e.g., S223R);
- 4) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 5) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at N115 (e.g., N115I); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R);
- 6) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at D121 (e.g., D121G); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 7) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at S128 (e.g., S128T); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 8) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at V131 (e.g., V131D); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R);
- 9) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at K219 (e.g., K219N); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R);
- 10) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S); and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at Q38 (e.g., Q38R);
- 11) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at N115 (e.g., N115I); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 12) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at D121 (e.g., D121G); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at S223 (e.g., S223R);
- 13) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at S128 (e.g., S128T); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 14) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at V131 (e.g., V131D); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 15) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at K219 (e.g., K219N); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 16) a variant of fHbp ID 22, where the fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S); and a variant of fHbp ID 55, where the fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K);
- 17) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at E92 (e.g., E92K); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 18) a first variant of fHbp ID 1, where the first fHbp ID 1 variant comprises an amino acid substitution at E92 (e.g., E92K); and a second variant of fHbp ID 1, where the second fHbp ID 1 variant comprises an amino acid substitution at S223 (e.g., S223R);
- 19) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at N115 (e.g., N115I); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at D211 (e.g., D211A);
- 20) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at N115 (e.g., N115I); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at K219 (e.g., K219N);
- 21) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at N115 (e.g., N115I); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S);
- 22) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at D121 (e.g., D121G); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S);
- 23) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at S128 (e.g., S128T); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S);
- 24) a first variant of fHbp ID 22, where the first fHbp ID 22 variant comprises an amino acid substitution at V131 (e.g., V131D); and a second variant of fHbp ID 22, where the second fHbp ID 22 variant comprises an amino acid substitution at G220 (e.g., G220S);
- 25) a first variant of fHbp ID 55, where the first fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K); and a second variant of fHbp ID 55, where the second fHbp ID 55 variant comprises an amino acid substitution at S223 (e.g., S223R);
- 26) a first variant of fHbp ID 55, where the first fHbp ID 55 variant comprises an amino acid substitution at E92 (e.g., E92K); and a second variant of fHbp ID 55, where the second fHbp ID 55 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 27) a variant of fHbp ID22 comprising amino acid substitutions: L130R and G133D and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at S223 (e.g., S223R);
- 28) a variant of fHbp ID22 comprising amino acid substitutions: L130R and G133D and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at H248 (e.g., H248L);
- 29) a variant of fHbp ID22 comprising amino acid substitutions: L130R, G133D, and K219N and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at S223 (e.g., S223R) or H248 (e.g., H248L); or
- 30) a variant of fHbp ID22 comprising amino acid substitutions: L130R, G133D, and G220S and a variant of fHbp ID 1, where the fHbp ID 1 variant comprises an amino acid substitution at S223 (e.g., S223R) or H248 (e.g., H248L).
Immunogenic compositions contemplated by the present disclosure include , but are not limited to, compositions comprising:
- 1) at least one variant fHbp of the present disclosure; and
- 2) NspA;where the fHbp and/or NspA can be provided as recombinant proteins and/or in a vesicle-based composition (e.g., OMV or MV). It should be noted that where the composition includes both NspA and a fHbp, the bactericidal activity of antibodies elicited by administration of the composition can result from cooperation of antibodies to one or both antigens. Examples of immunogenic compositions provided by the present disclosure include:
- a) an immunogenic composition that comprises a fHbp variant as described above (e.g., where the variant fHbp elicits a bactericidal antibody response to at least oneNeisseria meningitidis strain);
- b) an immunogenic composition that comprises a fHbp variant as described above (e.g., where the variant fHbp elicits a bactericidal antibody response to at least oneNeisseria meningitidis strain); and a recombinant NspA protein;
- c) an immunogenic composition that comprises a native OMV obtained from a genetically modified Neisseria host cell that is genetically modified with a nucleic acid encoding a variant fHbp of the present disclosure, such that the encoded variant fHbp is produced by the genetically modified host cell, where the OMV comprises the encoded variant fHbp; and
- d) an immunogenic composition that comprises a native OMV obtained from a genetically modified Neisseria host cell that is genetically modified with a nucleic acid encoding a variant fHbp of the present disclosure, such that the encoded non-naturally occurring fHbp is produced by the genetically modified host cell, where the OMV comprises the encoded variant fHbp; and where the Neisseria host cell also produces higher levels of NspA, such that the OMV also comprises NspA. For example, the Neisseria host cell can be one that is genetically modified for increased expression of NspA.
By "immunologically effective amount" is meant that the administration of that amount to an individual, either in a single dose, as part of a series of the same or different antigenic compositions, is effective to elicit an antibody response effective for treatment or prevention of a symptom of, or disease caused by, for example, infection by Neisseria, particularlyN.meningitidis, more particularly Group BN. meningitidis. This amount varies depending upon the health and physical condition of the individual to be treated, age, the capacity of the individual's immune system to produce antibodies, the degree of protection desired, the formulation of the vaccine, the treating clinician's assessment of the medical situation, and other relevant factors. It is expected that the amount will fall in a relatively broad range that can be determined through routine trials.
Amino acid sequences of NspA polypeptides are known in the art. See, e.g.,
WO 96/29412; and
Martin et al. (1997) J. Exp. Med. 185:1173; GenBank Accession No. U52066; and GenBank Accession No. AAD53286. An "NspA polypeptide" can comprise an amino acid sequence having at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, at least about 99%, or 100%, amino acid sequence identity to a contiguous stretch of from about 75 amino acids to about 100 amino acids, from about 100 amino acids to about 150 amino acids or from about 150 amino acids to about 174 amino acids, of the amino acid sequence depicted in
Figure 40 and set forth in SEQ ID NO:25. An "NspA polypeptide" can comprise an amino acid sequence having at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about98%, at least about 99%, or 100%, amino acid sequence identity to a contiguous stretch of from about 75 amino acids to about 100 amino acids, or from about 100 amino acids to about 155 amino acids, of amino acids 20 to 174 of the amino acid sequence depicted in
Figure 40 and set forth in SEQ ID NO:25. In some cases, the NspA polypeptide lacks a signal sequence; in other cases (e.g., for expression in a host cell), the NspA polypeptide includes a signal sequence.
Dosage regimen may be a single dose schedule or a multiple dose schedule (e.g., including booster doses) with a unit dosage form of the antigenic composition administered at different times. The term "unit dosage form," as used herein, refers to physically discrete units suitable as unitary dosages for human and animal subjects, each unit containing a predetermined quantity of the antigenic compositions of the present disclosure in an amount sufficient to produce the desired effect, which compositions are provided in association with a pharmaceutically acceptable excipient (e.g., pharmaceutically acceptable diluent, carrier or vehicle). The antigenic composition may be administered in conjunction with other immunoregulatory agents.
Antigenic compositions can be provided in a pharmaceutically acceptable excipient, which can be a solution such as a sterile aqueous solution, often a saline solution, or they can be provided in powder form. Such excipients can be substantially inert, if desired.
In some embodiments, a subject immunogenic composition comprises a subject fHbp present in a vesicle. In some embodiments, a subject immunogenic composition comprises a subject fHbp present in an MV. In some embodiments, a subject immunogenic composition comprises a subject fHbp present in an OMV. In some embodiments, a subject immunogenic composition comprises a mixture of MV and OMV comprising a subject fHbp. Vesicles, such as MV and OMV, are described above.
The antigenic compositions can further contain an adjuvant. Examples of known suitable adjuvants that can be used in humans include, but are not necessarily limited to, an aluminum adjuvant (e.g., aluminum phosphate, or aluminum hydroxide), MF59 (4.3% w/v squalene, 0.5% w/v Tween 80™, 0.5% w/v Span 85), a CpG-containing nucleic acid (where the cytosine is unmethylated), QS21, MPL, 3DMPL, extracts from Aquilla, ISCOMS, LT/CT mutants, poly(D,L-lactide-co-glycolide) (PLG) microparticles, Quil A, interleukins, and the like. For experimental animals, one can use Freund's adjuvant (incomplete Freund's adjuvant; complete Freund's adjuvant), N-acetyl-muramyl-L-threonyl-D-isoglutamine (thr-MDP), N-acetyl-nor-muramyl-L-alanyl-D-isoglutamine (CGP 11637, referred to as nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L-alanine-2-(1'-2'-dip- almitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine (CGP 19835A, referred to as MTP-PE), and RIBI, which contains three components extracted from bacteria, monophosphoryl lipid A, trehalose dimycolate and cell wall skeleton (MPL+TDM+CWS) in a 2% squalene/Tween 80 emulsion. The effectiveness of an adjuvant may be determined by measuring the amount of antibodies directed against the immunogenic antigen or antigenic epitope thereof.
Further exemplary adjuvants to enhance effectiveness of the composition include, but are not limited to: (1) oil-in-water emulsion formulations (with or without other specific immunostimulating agents such as muramyl peptides (see below) or bacterial cell wall components), such as for example (a) MF59 (
WO 90/14837;
Chapter 10 in Vaccine design: the subunit and adjuvant approach, eds. Powell & Newman, Plenum Press 1995), containing 5% Squalene, 0.5% Tween 80, and 0.5% Span 85 (optionally containing MTP-PE) formulated into submicron particles using a microfluidizer, (b) SAF, containing 10% Squalane, 0.4% Tween 80, 5% pluronic-blocked polymer L121, and thr-MDP either microfluidized into a submicron emulsion or vortexed to generate a larger particle size emulsion, and (c) RIBI adjuvant system (RAS), (Ribi Immunochem, Hamilton, Mont.) containing 2% Squalene, 0.2% Tween 80, and one or more bacterial cell wall components such as monophosphorylipid A (MPL), trehalose dimycolate (TDM), and cell wall skeleton (CWS), e.g., MPL+CWS (Detox TM); (2) saponin adjuvants, such as QS21 or Stimulon
™ (Cambridge Bioscience, Worcester, Mass.) may be used or particles generated therefrom such as ISCOMs (immunostimulating complexes), which ISCOMS may be devoid of additional detergent e.g.
WO 00/07621; (3) Complete Freund's Adjuvant (CFA) or Incomplete Freund's Adjuvant (IFA); (4) cytokines, such as interleukins (e.g. IL-1, IL-2, IL-4, IL-5, IL-6, IL-7, IL-12 (
WO99/44636), etc.), interferons (e.g. gamma interferon), macrophage colony stimulating factor (M-CSF), tumor necrosis factor (TNF), etc.; (5) monophosphoryl lipid A (MPL) or 3-O-deacylated MPL (3dMPL) e.g.
GB-2220221,
EP-A-0689454, optionally in the substantial absence of alum when used with pneumococcal saccharides e.g.
WO 00/56358; (6) combinations of 3dMPL with, for example, QS21 and/or oil-in-water emulsions e.g.
EP-A-0835318,
EP-A-0735898,
EP-A-0761231; (7) oligonucleotides comprising CpG motifs (see, e.g.,
WO 98/52581), e.g., an oligonucleotide containing at least one CG dinucleotide, where the cytosine is unmethylated; (8) a polyoxyethylene ether or a polyoxyethylene ester (see, e.g.
WO 99/52549); (9) a polyoxyethylene sorbitan ester surfactant in combination with an octoxynol (
WO 01/21207) or a polyoxyethylene alkyl ether or ester surfactant in combination with at least one additional non-ionic surfactant such as an octoxynol (
WO 01/21152); (10) a saponin and an immunostimulatory oligonucleotide (e.g. a CpG oligonucleotide) (
WO 00/62800); (11) an immunostimulant and a particle of metal salt e.g.
WO 00/23105; (12) a saponin and an oil-in-water emulsion e.g.
WO 99/11241; (13) a saponin (e.g. QS21)+3dMPL+IM2 (optionally+a sterol) e.g.
WO 98/57659; (14) other substances that act as immunostimulating agents to enhance the efficacy of the composition. Muramyl peptides include N-acetyl-muramyl-L-threonyl-D-isoglutamine (thr-MDP), N-25 acetyl-normuramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutarninyl-L-alanine-2-(1'-2'-dipalmitoyl-- sn-glycero-3-hydroxyphosphoryloxy)-ethylamine MTP-PE), etc. Adjuvants suitable for administration to a human are of particular interest. In some cases, the adjuvant is an aluminum salt adjuvant (e.g., aluminum phosphate or aluminum hydroxide).
The antigen compositions may contain other components, such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharin, talcum, cellulose, glucose, sucrose, magnesium, carbonate, and the like. The compositions may contain pharmaceutically acceptable auxiliary substances as required to approximate physiological conditions such as pH adjusting and buffering agents, toxicity adjusting agents and the like, for example, sodium acetate, sodium chloride, potassium chloride, calcium chloride, sodium lactate and the like.
The concentration of the subject fHbp in a formulation can vary widely (e.g., from less than about 0.1%, e.g., at or at least about 2% to as much as 20% to 50% or more by weight) and will usually be selected primarily based on fluid volumes, viscosities, and patient-based factors in accordance with the particular mode of administration selected and the patient's needs.
The fHbp-containing formulations can be provided in the form of a solution, suspension, tablet, pill, capsule, powder, gel, cream, lotion, ointment, aerosol or the like. It is recognized that oral administration can require protection of the compositions from digestion. This is typically accomplished either by association of the composition with an agent that renders it resistant to acidic and enzymatic hydrolysis or by packaging the composition in an appropriately resistant carrier. Means of protecting from digestion are well known in the art.
The fHbp-containing formulations can also be provided so as to enhance serum half-life of fHbp following administration. For example, where isolated fHbps are formulated for injection, the fHbp may be provided in a liposome formulation, prepared as a colloid, or other conventional techniques for extending serum half-life. A variety of methods are available for preparing liposomes, as described in, e.g.,
Szoka et al., Ann. Rev. Biophys. Bioeng. 9:467 (1980),
U.S. Pat. Nos. 4,235,871,
4,501,728 and
4,837,028. The preparations may also be provided in controlled release or slow-release forms.
The present disclosure provides a method of inducing an immune response to at least one Neisserial strain in a mammalian host. The methods generally involve administering to an individual in need thereof an effective amount of a subject immunogenic composition.
The fHbp-containing antigenic compositions are generally administered to a human subject that is at risk of acquiring a Neisserial disease so as to prevent or at least partially arrest the development of disease and its complications. An amount adequate to accomplish this is defined as a "therapeutically effective dose." Amounts effective for therapeutic use will depend on, e.g., the antigenic composition, the manner of administration, the weight and general state of health of the patient, and the judgment of the prescribing physician. Single or multiple doses of the antigenic compositions may be administered depending on the dosage and frequency required and tolerated by the patient, and route of administration.
The fHbp-containing antigenic compositions are generally administered in an amount effective to elicit an immune response, particularly a humoral immune response, e.g., a bactericidal antibody response, in the host. As noted above, amounts for immunization will vary, and can generally range from about 1 µg to 100 µg per 70 kg patient, usually 5 µg to 50 µg/70 kg. Substantially higher dosages (e.g. 10 mg to 100 mg or more) may be suitable in oral, nasal, or topical administration routes. The initial administration can be followed by booster immunization of the same of different fHbp-containing antigenic composition. Vaccination in some cases involves at least one booster, and in some cases two boosters.
In general immunization can be accomplished by administration by any suitable route, including administration of the composition orally, nasally, nasopharyngeally, parenterally, enterically, gastrically, topically, transdermally, subcutaneously, intramuscularly, in tablet, solid, powdered, liquid, aerosol form, locally or systemically, with or without added excipients. Actual methods for preparing parenterally administrable compositions will be known or apparent to those skilled in the art and are described in more detail in such publications asRemington's Pharmaceutical Science, 15th ed., Mack Publishing Company, Easton, Pa. (1980).
An anti-fHbp immune response can be assessed by known methods (e.g. by obtaining serum from the individual before and after the initial immunization, and demonstrating a change in the individual's immune status, for example an immunoprecipitation assay, an ELISA, or a bactericidal assay, a Western blot assay, or flow cytometric assay, or the like).
Whether a variant fHbp of the present disclosure elicits a bactericidal response to one or more strains ofN. meningitidis in a mammalian host can be determined using any well-known assay. For example, a human fH transgenic mouse can be used, where the mouse expresses human fH (e.g., human fH is present in serum of the mouse at a concentration of about 100 µg/ml or greater than 100 µg/ml). A variant fHbp of the present disclosure is administered to the human fH transgenic mouse. After a period of time, serum from the mouse is tested for bactericidal activity against one or more strains ofN. meningitidis. Suitable controls include, e.g., fHbp ID 1. An example of a suitable assay is described inVu et al. (2012) Sci. Reports 2:341.
The antigenic compositions can be administered to a mammalian host (e.g., a human subject) that is immunologically naive with respect toNeisseria meningitidis. In a particular embodiment, the subject is a human child about five years or younger, and preferably about two years old or younger, and the antigenic compositions are administered at any one or more of the following times: two weeks, one month, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 months, or one year or 15, 18, or 21 months after birth, or at 2, 3, 4, or 5 years of age.
It may be generally desirable to initiate immunization prior to the first sign of disease symptoms, or at the first sign of possible or actual exposure to infection or disease (e.g., due to exposure or infection by Neisseria).