What integrin ligands are found on the surface of activated endothelium?

Activated endothelium expresses specific integrin ligands that are crucial for mediating interactions with circulating leukocytes during the inflammatory response. In this case, ICAM-1 (Intercellular Adhesion Molecule 1), ICAM-2, and VCAM-1 (Vascular Cell Adhesion Molecule 1) are key players in the adhesion and migration of leukocytes from the bloodstream into tissues.

ICAM-1 and ICAM-2 engage with integrins like αLβ2 (LFA-1), facilitating the firm adhesion of leukocytes to the endothelium, which is especially important during inflammatory conditions. VCAM-1 binds to the integrin α4β1 (VLA-4), promoting the adhesion of lymphocytes and monocytes. The presence of these ligands on activated endothelial cells is vital for orchestrating leukocyte trafficking to sites of injury or inflammation, thus contributing to the overall immune response.

The other choices do not represent integrin ligands associated with activated endothelium. CD28 and CTLA-4 are co-stimulatory receptors involved in T-cell activation rather than ligands expressed on endothelial cells. Integrins α4β1 and αLβ2 mentioned in a different choice