Anti-Human CD45 (Clone 2D1) - Dylight® 550 (C897-GRP)

CD45 is a receptor protein tyrosine phosphatase involved in immune cell activation1. It is a large glycoprotein (180-220 kDa) with a broad range of expression in the animal kingdom, including mammals, chicken, shark, and mosquitoes. The cytoplasmic region of CD45 is highly conserved in mammals but its extracellular region varies between species. Additionally, differential splicing leads to several CD45 isoforms which can vary in glycosylation, which in turn can affect CD45 ligand interaction and function. In T cells, isoform expression is dependent on the stage of T cell maturation, activation, and differentiation. CD45 functions in the immunological synapse of the T cell-antigen presenting cell contact zone that is formed when T cells encounter cognate antigens presented by major histocompatibility (MHC) molecules 1. CD45 interacts with Src kinases, in particular Lck, to mediate antigen receptor signaling in T and B cells, and is required for the development and activation of lymphocytes. CD45 also interacts with CD3ζ and CD3ε chains as well as tyrosine kinase Zap 70, DAP12, the Janus kinase family, PAG, CD22, among others. With these interactions, CD45 functions to protect the host against viral, bacterial, and fungal infections. Certain variants of CD45 are associated with autoimmune disease and dysregulation is observed in some cancers 1. CD45 has been explored as a target of therapeutic modulation for organ transplantation 1, 2 , autoimmune disease 1, bone marrow transfusion 3, 4, 5, 6 as well as cancer radioimmunotherapy 7, 8, including a bispecific antibody targeting CD45 and 90 Y-DOTA for therapy of myeloid leukemia 9. 2D1 was generated by immunizing BALB/c mice with human peripheral blood mononuclear cells 10, 11. Spleen cells were fused to the P3/NSI/I-Ag4-1 myeloma line and resulting supernatants screened by an indirect I125 labeled antiglobulin binding assay. CD45 is also known as leukocyte common antigen (LCA), lymphocyte antigen 5 (Ly-5), and T200 12. 2D1 is also known as anti-HLe-1 10, 11.