The CD81 molecule is a single chain, 4 transmembrane domain protein (Tetraspan/TM4SF). Both the NH2- and COOH-termini are located inside the cytoplasm, and two loops of the protein sequence are exposed extracellularly. The CD81 antigen is not glycosylated and its molecular weight is 26 kDa. Its tissue distribution is broad. This antigen may be present in some cases as multimolecular complexes, in association with other members of the TM4 superfamily (CD37, CD53) or, on the surface of B cells, in association with CD19 and/or CD21 and/or MHC class II antigens. Most B lymphocytes, at all stages of cellular differentiation, express CD81 at relatively high levels.
|Clone: JS64||Isotype: IgG2a Mouse|
|The JS64 antibody reacts with the majority of normal lymphocytes, monocytes and eosinophils. Neutrophils and platelets are negative. JS64 has an anti-proliferative effect on some cell lines, but does not cause apoptosis.