Integrin alpha-V beta-3, alpha-V beta-5, alpha-5 beta-1, and alpha-M beta-2 receptors (αVβ3, αVβ5, α5β1, αMβ2)

Integrins are a superfamily of cell adhesion heterodimeric transmembrane receptors, each consisting of specific alpha and beta subunits, that mediate cell–cell and cell–extracellular matrix interactions. While presented together in this summary, Integrin alpha-V beta-3, alpha-V beta-5, alpha-5 beta-1, and alpha-M beta-2 receptors are distinct molecular entities with unique binding specificities and tissue distributions. Integrin alpha-V beta-3 and alpha-V beta-5 are RGD-binding receptors recognized for their roles in angiogenesis, tumor invasion, and regulation of cell migration through binding to vitronectin, fibronectin, osteopontin, and other ECM proteins. Integrin alpha-5 beta-1 is the main fibronectin receptor, playing a central role in development, cell adhesion, migration, and ECM structure. Integrin alpha-M beta-2 (Mac-1, CR3) is primarily expressed on myeloid and certain immune cells, mediating leukocyte adhesion, migration, and phagocytosis in inflammation and immune responses. Each integrin plays distinct and overlapping biological roles, and several are actively pursued as drug targets in oncology, fibrosis, and immune-related diseases, although clinical translation has been challenging due to on-target adverse effects and context-specific biology.

Other names

vitronectin receptorfibronectin receptorMac-1CR3 (complement receptor 3)

Competitive inhibition of ligand (RGD motif-containing proteins like fibronectin or vitronectin) binding Antagonism of integrin-mediated cell adhesion, migration, and survival Modulation or inhibition of downstream signaling pathways involved in proliferation, migration, and immune activation