MCAM/CD146

MCAM, the CD146 antigen, is a cell adhesion molecule of the immunoglobulin superfamily carrying five extracellular Ig-like domains. It was originally characterized on melanoma cells as a promoter of metastatic spread, and it is also expressed on melanocytes and perivascular mural cells. On endothelium MCAM localizes to intercellular junctions, where it participates in barrier organization and permeability control, and it marks the pericyte-containing fraction of stromal vascular cells. The antigen contributes to angiogenesis and vascular stability, and its expression patterns have made it a subject of interest in tumor progression, endothelial biology and mesenchymal stromal cell characterization.