Invitrogen™ CD45R (B220) Monoclonal Antibody (RA3-6B2), PE, eBioscience™, Invitrogen™

CD45R (PTPRC) is a member of the protein tyrosine phosphatase (PTP) family. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. CD45 contains an extracellular domain, a single transmembrane segment and two tandem intracytoplasmic catalytic domains. CD45 is specifically expressed in hematopoietic cells and has been shown to be an essential regulator of T- and B-cell antigen receptor signaling. CD45 glycoprotein is crucial in lymphocyte development and antigen signaling, serving as an important regulator of Src-family kinases. CD45 protein exists in multiple isoforms as a result of alternative splicing, and these isoforms differ in their extracellular domains, but share identical transmembrane and cytoplasmic domains. Further, these CD45 isoforms differ in their ability to translocate into the glycosphingolipid-enriched membrane domains and their expression depends on cell type and physiological state of the cell. In addition to its role in immunoreceptor signaling, CD45 is important in promoting cell survival by modulating integrin-mediated signal transduction pathway and is also involved in DNA fragmentation during apoptosis. CD45RA is an isoform of the CD45 complex and has restricted expression between different subtypes of lymphoid cells. Diseases associated with CD45 dysfunction include Severe Combined Immunodeficiency (T-cell negative, B-Cell Negative) and Hepatitis C.