The mAb I3/2.3 recognizes mouse CD45, which is also known as the leukocyte common antigen (L-CA or LCA), T200, or Lymphocyte antigen 5 (Ly-5). CD45 is a 180-240 kDa single-pass type I transmembrane glycoprotein that is encoded by Ptprc (protein tyrosine phosphatase, receptor type, C) which belongs to the protein tyrosine phosphatase (PTP) family. CD45 is variably expressed on thymocytes and other hematopoietic cells except mature erythrocytes and platelets. Different isoforms of CD45 arise from alternative splicing of variable exons 4, 5, and 6, which encode A, B, and C determinants, respectively, that encode extracellular domains of the transmembrane receptor. The differential expression of these isoforms is related to the cell's lineage as well as its state of activation and maturation. The mAb I3/2.3 reportedly recognizes all CD45 isoforms. CD45 plays key roles as a protein tyrosine-protein phosphatase in leucocyte responses including signal pathways transduced by antigen specific receptors expressed on T cells (TCRs) and B cells (BCRs).
This antibody is conjugated to BD Horizon BV605 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max of 602-nm, BD Horizon BV605 can be excited by a violet laser and detected with a standard 610/20-nm filter set. BD Horizon BV605 is a tandem fluorochrome of BD Horizon BV421 and an acceptor dye with an Em max at 605-nm. Due to the excitation of the acceptor dye by the green (532 nm) and yellow-green (561 nm) lasers, there will be significant spillover into the PE and BD Horizon PE-CF594 detectors off the green or yellow-green lasers. BD Horizon BV605 conjugates are very bright, often exhibiting brightness equivalent to PE conjugates and can be used as a third color off of the violet laser.