ITGAL
Description
The ITGAL (integrin subunit alpha L) is a protein-coding gene located on chromosome 16.
ITGAL, also known as integrin alpha L, CD11a, or lymphocyte function-associated antigen 1 (LFA-1) alpha polypeptide, is a protein encoded by the ITGAL gene in humans. It plays a critical role in the immune system, participating in cellular adhesion and costimulatory signaling. ITGAL combines with the ITGB2 beta chain to form LFA-1, expressed in all leukocytes. LFA-1 mediates leukocyte intercellular adhesion through interactions with ICAMs 1-3 and is involved in lymphocyte costimulatory signaling. Efalizumab, a drug targeting CD11a, acts as an immunosuppressant but was withdrawn due to severe side effects.
ITGAL/ITGB2 acts as a receptor for ICAM1, ICAM2, ICAM3, and ICAM4. It also binds to F11R and the secreted form of ISG15, an ubiquitin-like protein, with ITGAL mediating the interaction. ITGAL/ITGB2 is involved in a range of immune processes, including leukocyte-endothelial cell interaction, cytotoxic T-cell mediated killing, and antibody-dependent killing by granulocytes and monocytes. It contributes to natural killer cell cytotoxicity and facilitates leukocyte adhesion and transmigration of leukocytes, including T-cells and neutrophils. ITGAL/ITGB2 is essential for the generation of common lymphoid progenitor cells in bone marrow, indicating its role in lymphopoiesis. In association with ICAM3, ITGAL/ITGB2 contributes to apoptotic neutrophil phagocytosis by macrophages.
ITGAL is also known as CD11A, LFA-1, LFA1A.
