Human Intercellular Adhesion Molecule 3 (ICAM3) Protein

Background

Intercellular Adhesion Molecule 3 (ICAM3), also known as CD50, is a member of the immunoglobulin superfamily (IgSF) that plays a crucial role in cell-cell adhesion and immune system regulation. It is expressed predominantly on leukocytes, especially resting lymphocytes, and interacts with integrins to mediate various immune responses, including leukocyte trafficking, T-cell activation, and antigen recognition. ICAM3 is particularly involved in the early stages of immune responses, functioning as a ligand for leukocyte function-associated antigen-1 (LFA-1), an integrin found on T cells and other leukocytes. ICAM-3 acts as a facilitator of immunological synapse formation, helping leukocytes adhere to antigen-presenting cells and promoting signaling pathways critical for immune activation. Its interaction with integrins also promotes adhesion between leukocytes and endothelial cells, an important step in the migration of immune cells to sites of inflammation or infection. ICAM-3 is essential in regulating leukocyte dynamics and activation during immune surveillance and host defense.