Anti-CD46 (Membrane Cofactor Protein) Monoclonal Antibody (Clone: MCP/931)

Recognizes a protein of 52kDa-58kDa, identified as CD46. CD46 exists as many isoforms in a variety of tissues. It is strongly expressed on salivary gland ducts and kidney ducts, moderately on lymphocytes and endothelium, and weakly on interstitial tissues and muscle cells, but not on erythrocytes. CD46 functions as a C3b/C4b-binding glycoprotein that inhibits complement activation on host cells. It also serves as a measles virus receptor, an adherence factor for group A Streptococcus pyogenes, and a cellular pilus receptor for pathogenic Neisseria. Protein function: Acts as a cofactor for complement factor I, a serine protease which protects autologous cells against complement-mediated injury by cleaving C3b and C4b deposited on host tissue. May be involved in the fusion of the spermatozoa with the oocyte during fertilization. Also acts as a costimulatory factor for T-cells which induces the differentiation of CD4+ into T-regulatory 1 cells. T-regulatory 1 cells suppress immune responses by secreting interleukin-10, and therefore are thought to prevent autoimmunity. [The UniProt Consortium]