LFA-1

LFA-1 stands for Lymphocyte function-associated antigen-1.

LFA-1 is found on all T-cells and also on B-cells, macrophages and neutrophils and is involved in recruitment to the site of infection. It binds to ICAM-1 on antigen-presenting cells and functions as an adhesion molecule, it is the first to bind T-cells to antigen-presenting cells and initially binds weakly. A signal from the T-cell receptor changes the conformation and prolongs the cell contact, allowing the T-cell to proliferate.

LFA-1 is part of the family of leukocyte integrins which are recognised by their common β-chains (CD18). LFA-1 also has a distinct α-chain (CD11a).