CD20

Size

£659.00

SKU:: 168958
Purity:: Purified
Storage Conditions:: -20°C
Supplier:: United States Biological
Host:: Mouse
Immunogen:: Daudi cells
Clone:: NKI-B20/1
Format:: Supplied as a liquid in 0.09% sodium azide.
Extra Details:: The antigen recognized by CD20 MAbs is a 35-37 kDa non-glycosylated phosphoprotein, that may function as a Ca2+ ion channel. The protein structure deduced from cloned DNA sequence suggests that the CD20 antigen is a transmembrane protein that passes the membrane four times, with both the C- and the N-terminus on the cytoplasmic side and only a small part exposed on the cell surface. Expression of CD20 antigen is specific for B lymphocytes and is present during most differentiation stages, beginning at the early pre-B cell stage and disappearing upon differentiation into plasma cells. The CD20 molecule appears to be involved in the activation and cell cycle progression of B lymphocytes. Stimulating as well as inhibitory effects in different phases of the cell cycle have been reported for different CD20 MAbs. Pokeweed mitogen induced differentiation of B lymphocytes into Ig-producing cells is inhibited by CD20 MAbs. The CD20 antigen is also expressed on most malignant B cells. In agreement with the expression during normal B cell differentiation, all malignancies of mature B cells are CD20 positive, but early pre-B ALL cells often lack CD20 antigen. The restriction of its expression to B lineage cells, together with the lack of expression on progenitor cells, makes CD20 antigen an interesting target for (antibody-based) immunotherapy for B cell lymphoid malignancies. Moreover, CD20 antigen is expressed at relatively high density on most normal and malignant B cells and it is not susceptible to antibody induced modulation. NKI-B20/1 can induce antibody-dependent cell-mediated cytotoxicity (ADCC) with rIL-2-activated NK cells from mouse spleen. Here the antigen density seemed the most important factor in determining the level of cell kill. Also with mouse peritoneal macrophages as effector cells NKI-B20/1 mediates cytotoxicity. For this IgG1 variant of NKI-B20 this is at variance to what has been reported for MAbs of other specificities. Despite the high activity with murine effector cells, the NIK-B20/1 MAb does not mediate ADCC with human peripheral blood NK cells, with or without stimulation with rIL-2, due to the lack of interaction of the murine MAb with the human Fc receptor. The CD20 antigen appears to be a good target antigen for various forms of cytotoxicity, to which its relatively high antigenic density, its resistance to antibody-induced modulation, and its unusual structure all contribute. Applications: Suitable for use in Flow Cytometry, ELISA, Immunoprecipitation and Immunohistochemistry. Other applications not tested. Recommended Dilution: Optimal dilutions to be determined by the researcher. Hybridoma: Sp2/0 myeloma cells with spleen cells from Balb/c mice. Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.

Shipping Conditions:: Blue Ice