May function in mediating immune cell-cell interactions. May act as a T-cell costimulatory molecule, enhancing anti-CD3-induced proliferation. May play a role in the interaction of dendritic cells with T-cells and the cells of the adaptive immune response.
Subcellular locations: Cell membrane
Expressed in spleen, lymph node, and tonsil. Lower expression in peripheral blood, bone marrow, and colon. No expression detected in thymus. Highly expressed in dendritic and B-cells.