Anti-CD20, monoclonal

CD20 is a non glycosylated protein with a molecular weight of 35 or 37 kDa depending on the degree of phosphorylation. Although not a member of the tetraspanin superfamily of cell surface receptors, it crosses the cell membrane four times. The CD20 antigen is present on human pre B lymphocytes and on B lymphocytes at all stages of maturation, except on plasma cells. Low level expression of the CD20 antigen has been detected on normal T lymphocytes. The CD20 molecule is involved in regulation of B cell differentiation, presumably via its reported function as a Ca2+ channel subunit. Protein Function: B-lymphocyte-specific membrane protein that plays a role in the regulation of cellular calcium influx necessary for the development, differentiation, and activation of B-lymphocytes (PubMed:12920111, PubMed:3925015, PubMed:7684739). Functions as a store-operated calcium (SOC) channel component promoting calcium influx after activation by the B-cell receptor/BCR (PubMed:12920111, PubMed:18474602, PubMed:7684739) [The Uniprot Consortium]