分子量:22.3 kDa

纯度:>90% as determined by SDS-PAGE.

内毒素:Less than 1.0 EU per μg of the Human MS4A1 Protein, His Tag by the LAL method.

Buffer:PBS, pH7.4

生物活性:

产品特性:Human MS4A1 Protein, His Tag is fused with trxA tagged polyhistidine tag at the N-terminus, and has a calculated MW of 22.3 kDa. The predicted N-terminus is Met. The reducing (R) protein migrates as 25 kDa in SDS-PAGE .

产品背景:B-lymphocyte antigen CD20  is also known as B-lymphocyte surface antigen B1, Leukocyte surface antigen Leu-16, Membrane-spanning 4-domains subfamily A member 1 and MS4A1, is an activated-glycosylated phosphoprotein expressed on the surface of all B-cells beginning at the pro-B phase (CD45R+, CD117+) and progressively increasing in concentration until maturity. CD20 is expressed on all stages of B cell development except the first and last; it is present from late pro-B cells through memory cells, but not on either early pro-B cells or plasma blasts and plasma cells. It is found on B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. The protein has no known natural ligand and its function is to enable optimal B-cell immune response, specifically against T-independent antigens. It is suspected that it acts as a calcium channel in the cell membrane. CD20 / MS4A1 is the target of the monoclonal antibodies (mAb) rituximab, Ibritumomab tiuxetan, and tositumomab, which are all active agents in the treatment of all B cell lymphomas and leukemias. Defects in CD20 / MS4A1 are the cause of immunodeficiency common variable type 5 (CVID5); also called antibody deficiency due to CD20 defect. CVID5 is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen.