CD11a, also known as integrin αL or LFA-1 (lymphocyte function-associated antigen-1), is a member of the β2 family of integrins that includes Mac-1 and p150,95. It is composed of two noncovalently linked α and β chains which are associated with the actin cytoskeleton. CD11a (integrin αL) has been reported to be expressed on the surface of T cells, neutrophils, and macrophages. It is involved in cell-cell adhesion and it also conveys signals from the plasma membrane to the cytoplasm. Activation of the TCR/CD3 complex on T cells transmits intracellular signals that activate integrin αL ("inside-out" signaling). This results in the conformational change of integrin αL, which increases its affinity for its ligand ICAM-1,-2, and -3. Furthermore, this signaling releases integrin αL from the actin cytoskeleton, resulting in clustering of this surface molecule. The high affinity conformation and the clustering of integrin αL increases the adhesion between it and ICAM. This adhesion is essential for leukocyte activation and results in "outside-in" signaling which induces the polymerization of actin, thereby stabilizing the integrin αL-ICAM interaction. This interaction is necessary for CTL and NK mediated killing, T and B cell responses, ADCC, and immune cell extravasation.
This antibody is routinely tested by western blot analysis. Other applications were tested at BD Biosciences Pharmingen during antibody development only or reported in the literature.