Lymph capillaries orlymphatic capillaries are tiny, thin-walledmicrovessels located in the spaces betweencells (except in thecentral nervous system and non-vasculartissues) which serve to drain and processextracellular fluid. Upon entering thelumen of a lymphatic capillary, the collected fluid is known aslymph. Each lymphatic capillary carries lymph into alymphatic vessel, which in turn connects to alymph node, a small bean-shaped gland that filters and monitors the lymphatic fluid for infections.^[1] Lymph is ultimately returned to thevenous circulation.

Lymph capillary
Diagram showing the formation oflymph frominterstitial fluid (labeled here as "Tissue fluid")
Details
System	Lymphatic system
Identifiers
Latin	vas lymphocapillare
TA98	A12.0.00.044
TA2	3918
TH	H3.09.02.0.05004
FMA	5028
Anatomical terminology [edit on Wikidata]

Lymphatic capillaries are slightly larger in diameter thanblood capillaries, and have closed ends (unlike the loop structure of blood capillaries). Lymph capillaries are strategically placed among the blood-related capillaries in order to have efficient and effective uptake from the interstitial fluid during capillary exchange. This intentional formation allows for a more rapid and continuous collection.^[2] Their unique structure permitsinterstitial fluid to flow into them but not out. The ends of theendothelial cells that make up the wall of a lymphatic capillary overlap. When pressure is greater in the interstitial fluid than in lymph, the cells separate slightly, like the opening of a one-way swinging door, and interstitial fluid enters the lymphatic capillary. When pressure is greater inside the lymphatic capillary, the cells adhere more closely, and lymph cannot escape back into the interstitial fluid. Attached to the lymphatic capillaries are anchoring filaments, which contain elastic fibers. They extend out from the lymphatic capillary, attaching lymphatic endothelial cells to surrounding tissues. When excess interstitial fluid accumulates and causes tissue swelling, the anchoring filaments are pulled, making the openings between cells even larger so that more fluid can flow into the lymphatic capillary.^[3]

Lymph capillaries have a greater internaloncotic pressure than blood capillaries, due to the greater concentration ofplasma proteins present.

In the small intestine, lymphatic capillaries calledlacteals are critical for the transport of dietary lipids and lipid-soluble vitamins to the bloodstream. In the small intestine, dietarytriglycerides combine with other lipids and proteins, and enter the lacteals to form a milky fluid calledchyle. The chyle then travels through the lymphatic system, eventually entering the bloodstream.^[4]