Junctional adhesion molecule-C (JAM-C) also known as JAM-2 is a 45 kD cell adhesion molecule (CAM). JAM-C is a transmembrane protein which is a member of the immunoglobulin superfamily found at intercellular junctions of endothelial cells. JAM-C belongs together with JAM-A (JAM or JAM-1) and JAM-B (VE-JAM or JAM-3) to a family of adhesion proteins with a V-C2 immunoglobulin domain organization. JAM plays an important role in tight junctions where it is involved in cell-to-cell adhesion through homophilic interaction. It codistributes with other tight junction components as ZO-1, 7H6 antigen, cingulin and occludin. JAM-C is potentially involved in the junctional sealing of the vascular endothelium, in particular of high endothelial venules (HEV). In adult murine tissue JAM-C expression is reported to be restricted to high endothelial venules of lymphoid organs, lymphoendothelial cells and endothelial cells in kidney. Monoclonal antibody CRAM-19 H36 also reacts with human JAM-C. In humans, JAM-C expression is not restricted to endothelial cells, but is also expressed on human lymphocytes.