CD44 Rat anti-Mouse, Brilliant Violet 650, Clone: IM7, BD Optibuild™

Description

• The IM7 antibody specifically recognizes an epitope on both alloantigens and all isoforms of the CD44 glycoprotein (Pgp-1, Ly-24)
• The standard form of CD44, lacking variable exons and referred to as CD44H or CD44s, is widely expressed on hematopoietic and non-hematopoietic cells
• CD44 isoforms encoded by variable exons are expressed on epithelial cells, but only at low levels on most leukocytes
• Mice with the Ly-24.1 alloantigen (e.g., BALB/c, CBA/J, DBA/1, DBA/2) have relatively large subsets of CD44H+ T lymphocytes, while Ly-24.2 strains (e.g., A, AKR, CBA/N, C3H/He, C57BL, C57BR, C57L, C58, NZB, SJL, SWR, 129) have fewer CD44H+ T cells
• CD44 is a cell adhesion receptor, and its principal ligand, hyaluronate, is a common component of extracellular matrices
• Differential glycosylation of CD44 influences its binding to hyaluronate
• Additional ligands include the cell surface form of CD74 and the cytokine osteopontin (Eta-1)
• Bone marrow- and thymus-derived progenitor cells capable of repopulating the thymus express CD44
• In the periphery, the level of CD44 expression increases upon activation of B lymphocytes, CD4+ T cells, and CD8+ T cells; memory cells can be recognized by their CD44[hi] phenotype
• The IM7 mAb inhibits established collagen-induced arthritis in DBA/1 mice
• Moreover, it prevents CNS inflammation and clinical symptoms of experimental autoimmune encephalomyelitis
• In contrast, the same antibody exacerbates experimental autoimmune thyroiditis in CBA/J mice
• The IM7 mAb recognizes a different epitope from that recognized by mAb KM114, and the antibody pair can be used in ELISA to detect soluble CD44
• It has been observed that IM7 antibody crossreacts with human, dog, cat, horse, cow, and pig leukocytes
• Anti-human CD44, clone G44-26, and IM7 antibody compete for binding to human peripheral blood lymphocytes
• The antibody was conjugated to BD Horizon™ BV650 which is part of the BD Horizon Brilliant™ Violet family of dyes
• This dye is a tandem fluorochrome of BD Horizon BV421 with an Ex Max of 405-nm and an acceptor dye with an Em Max at 650-nm
• BD Horizon BV650 can be excited by the violet laser and detected in a filter used to detect APC-like dyes (eg, 660/20-nm filter)
• Due to the excitation and emission characteristics of the acceptor dye, there will be spillover into the APC and Alexa Fluor™ 700 detectors
• However, the spillover can be corrected through compensation as with any other dye combination.