CD200 Protein

Quality Statement:
CD200 is a type-1 cell membrane glycoprotein of the immunoglobulin supergene family, present on both cells with myeloid/lymphoid origin as well as on epithelial cells and many cancer cells. CD200, also known as MRC OX-2, is a highly conserved, 48 kDa type 1a transmembrane glycoprotein related structurally to the B7 family of costimulatory receptors. The molecule itself consists of an IgSF extracellular domain (single V + C), a single transmembrane region and a short cytoplasmic tail lacking signaling motifs. The molecule is expressed by resting dendritic cells, thymocytes, endothelial cells, neurons and osteoblast precursors (OBp), as well as by activated B and T cells (including αβTCR+ and most γδTCR+ cells). CD200 interacts with a structurally related receptor (CD200R) expressed mainly on myeloid cells and is involved in regulation of macrophage and mast cell function. OX-2 / CD200 and CD200R associate via their respective N-terminal Ig-like domains. CD200 also plays an important role in prevention of graft rejection, autoimmune diseases and spontaneous abortion.

Reference:
1．\tBarclay A.N., Wright G.J., Brooke G., Brown M.H. CD200 and membrane protein interactions in the control of myeloid cells. Trends Immunol. 2002; 23:285-290. doi: 10.1016/S1471-4906(02)02223-8.2．\tWright G.J., Puklavec M.J., Willis A.C., Hoek R.M., Sedgwick J.D., Brown M.H., Barclay A.N. Lymphoid/Neuronal cell surface OX2 glycoprotein recognizes a novel receptor on macrophages implicated in the control of their function. Immunity. 2000; 13:233-242. doi: 10.1016/S1074-7613(00)00023-6.3．\tMoreaux J., Veyrune J.L., Reme T., De Vos J., Klein B. CD200, A putative therapeutic target in cancer. Biochem. Biophys. Res. Commun. 2008;366:117-122. doi: 10.1016/j.bbrc.2007.11.103.4．\tBarclay A.N. Different reticular elements in rat lymphoid tissue identified by localization of IA, Thy-1 and MRC OX-2 antigens. Immunology. 1981;44:727-736.