Clone MT4 reacts with the 190, 205 and 220 kDa isoforms of the cell-surface antigen CD45RB. Variations in CD45RB expression can discriminate between Th1 and Th 2 cells, i.e. CD45RBbright and CD45RB-dim respectively [8]. CD45RB bright expression on T cells correlates with higher proliferation and IFN-g production in comparison to CD45RB dim expression. 90 % of lymphocytes are CD45RB positive. Other isoforms can be detected using anti-CD45RA (clone MB1, cat.no. AM39020), or anti-CD45RC (clone MT2, cat.no. AM39022).
The CD45 Molecule is also known as the Leukocyte Common Antigen (LCA) or T200 antigen, and is comprised of different glycoproteins ranging from 180-240 kD [1,2]. CD45 is a family of transmembrane protein tyrosine phosphatases critically involved in the regulation of lymphocyte activation signals. Expression of CD45 is found on all hemopoietic cells, e.g. granulocytes, monocytes, macrophages and lymphocytes, except mature erythroid cells. In humans, there is heterogeneous expression of CD45 isoforms (RA, RB, RO, RC) on lymphocyte subpopulations. Detection of the different isoforms can distinguish, for example, between naive T cells and memory T cells, which is of interest in patients with immunodeficiency and autoimmune diseases.Synonyms: L-CA, Leukocyte common antigen, PTPRC, Receptor-type tyrosine-protein phosphatase C, T200