Integrin, alpha E (ITGAE) also known asCD103 (cluster ofdifferentiation103) is anintegrin protein that in human is encoded by theITGAEgene.[5][6] CD103 binds integrin beta 7 (β7–ITGB7) to form the complete heterodimeric integrin molecule αEβ7, which has no distinct name. The αEβ7 complex is often referred to as "CD103" though this strictly refers only to the αE chain. Note that the β7 subunit can bind with other integrin α chains, such as α4 (CD49d).
The chief ligand for αEβ7 isE-cadherin, a cellular adhesion molecule (CAM) found onepithelial cells.[11] It is probably important for T cell homing to the intestinal sites[12] and thymocyte contacts with thymic reticuloepithelial cells.[13]
Tregs are important for decreasing the immune response and appear to play a crucial role in the prevention ofautoimmune diseases. Tregs are defined asCD4+/CD25+/Foxp3+ cells.[14] Some CD4+/FoxP3− cells also expressCD103 and have been attributed regulatory activity. It is unclear whether the presence of CD103 on Treg cells represents a specialized feature for Treg, or Treg differentiation of IEL T cells.
^Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, et al. (2008).WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (World Health Organization Classification of Tumours) (4th ed.). Geneva: World Health Organization.ISBN978-92-832-2431-0.
^Agace WW, Higgins JM, Sadasivan B, Brenner MB, Parker CM (October 2000). "T-lymphocyte-epithelial-cell interactions: integrin alpha(E)(CD103)beta(7), LEEP-CAM and chemokines".Current Opinion in Cell Biology.12 (5):563–568.doi:10.1016/S0955-0674(00)00132-0.PMID10978890.
^Kutlesa S, Wessels JT, Speiser A, Steiert I, Müller CA, Klein G (December 2002). "E-cadherin-mediated interactions of thymic epithelial cells with CD103+ thymocytes lead to enhanced thymocyte cell proliferation".Journal of Cell Science.115 (Pt 23):4505–4515.doi:10.1242/jcs.00142.PMID12414996.S2CID14571087.
^Allakhverdi Z, Fitzpatrick D, Boisvert A, Baba N, Bouguermouh S, Sarfati M, et al. (December 2006). "Expression of CD103 identifies human regulatory T-cell subsets".The Journal of Allergy and Clinical Immunology.118 (6):1342–1349.doi:10.1016/j.jaci.2006.07.034.PMID17137867.
Liu YH, Chen RH, Chen WC, Tsai Y, Wan L, Tsai FJ (August 2010). "Disease association of the CD103 polymorphisms in Taiwan Chinese Graves' ophthalmopathy patients".Ophthalmology.117 (8):1645–1651.doi:10.1016/j.ophtha.2009.12.037.PMID20417566.
Lesch KP, Timmesfeld N, Renner TJ, Halperin R, Röser C, Nguyen TT, et al. (November 2008). "Molecular genetics of adult ADHD: converging evidence from genome-wide association and extended pedigree linkage studies".Journal of Neural Transmission.115 (11):1573–1585.doi:10.1007/s00702-008-0119-3.PMID18839057.S2CID7036114.
Heron M, Grutters JC, Van Moorsel CH, Ruven HJ, Kazemier KM, Claessen AM, et al. (October 2009). "Effect of variation in ITGAE on risk of sarcoidosis, CD103 expression, and chest radiography".Clinical Immunology.133 (1):117–125.doi:10.1016/j.clim.2009.06.007.PMID19604725.
Shaw SK, Brenner MB (October 1995). "The beta 7 integrins in mucosal homing and retention".Seminars in Immunology.7 (5):335–342.doi:10.1016/1044-5323(95)90014-4.PMID8580465.
Heron M, Slieker WA, Zanen P, van Lochem EG, Hooijkaas H, van den Bosch JM, et al. (March 2008). "Evaluation of CD103 as a cellular marker for the diagnosis of pulmonary sarcoidosis".Clinical Immunology.126 (3):338–344.doi:10.1016/j.clim.2007.11.005.PMID18182176.
