CD20抗体说明书

B lymphocytes marker

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 Ca++ channel subunit.
Function : This protein may be involved in the regulation of B-cell activation and proliferation
Subcellular Location : Membrane; Multi-pass membrane protein.
Tissue Specificity : Expressed on B-cells.
Post-translational modifications : Phosphorylated. Might be functionally regulated by protein kinase(s).
DISEASE : Defects in MS4A1 are the cause of immunodeficiency common variable type 5 (CVID5) [MIM:613495]; 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. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low.
Similarity : Belongs to the MS4A family.

[PHARMACEUTICAL] Monoclonal antibodies (mAb) against CD20 are used to treat B-cell non-Hodgkin lymphoma (NHL). These antibodies include Rituximab (Mabthera), Britumomab (Zevalin) and Tositumomab (Bexxar). CD20 engaged by mAb can generate transmembrane signals capable of directly controlling cell growth and triggering cell death in certain tumors. Alternatively, mAb can mediate complement-dependent cytotoxicity.

B淋巴细胞标志物

CD20是B细胞特异性抗原，其表达呈细胞类型一种质膜蛋白质，参与信号传导作用，此抗体识别大多数B细胞上的一种抗原。多用于标记B淋巴细胞及B细胞淋巴瘤。
CD20一般不与T细胞交叉反应，对B细胞淋巴瘤和急慢性淋巴细胞白血病等有较好的细胞特异性，因此在恶性淋巴瘤，尤其是T或B细胞淋巴瘤的分类上，CD20是最常用的B细胞标志。