Recombinant human CD200 protein

CD200, also known as OX-2 membrane glycoprotein isoform a, belongs to the immunoglobulin superfamily. This protein imparts immune privileges by suppressing alloimmune and autoimmune responses through its receptor, CD200R, expressed primarily on myeloid cells. D200 and CD200R associate via their respective N-terminal Ig-like domains. CD200-CD200R signaling have been shown to play an important role in the regulation of anti-tumor immunity, and overexpression of CD200 has been reported in a number of malignancies, including CLL, as well as on cancer stem cells. Studies of the related genes in mouse and rat suggest that this gene may regulate myeloid cell activity and delivers an inhibitory signal for the macrophage lineage in diverse tissues. Elevated expression of this protein has been reported to be associated with poor prognosis in a number of human malignancies. In addition, it also plays an important role in prevention of graft rejection, autoimmune diseases and spontaneous abortion. Recombinant human CD200 protein, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.