CD44std Monoclonal Antibody (SFF-2), FITC, eBioscience™, Invitrogen™

Description

• Description: BMS113 specifically recognizes human standard CD44, but cannot be used to distinguish between splice variants (exon v3-v10)
• CD44 is a cell membrane associated, polymorphic glycoprotein with apparent molecular weights ranging from 85 kDa to 250 kDa
• CD44 isoforms participate in a wide variety of cell-cell or cell-matrix interactions including lymphocyte homing, establishment of B and T cell immune responses, tumor metastases formation and inflammation
• Three isoform categories of the CD44 molecule have been identified: 1) an 80-90 kDa isoform, the so-called standard form named CD44std, which is widely distributed on several hematopoietic and nonhemato-poietic cells including all subsets of leukocytes, monocytes, erythrocytes, many types of epithelium, mesenchymal elements like fibroblasts, smooth muscle cells and glial cells of the central nervous system, 2) a medium size category of 110-160 kDa which is weakly expressed on epithelial cells and highly expressed in some carcinomas and 3) a category which includes very large isoforms of 250 kDa covalently modified by the addition of chondroitin sulfate
• These bigger isoforms of CD44 arise by alternative splicing of one or more variant exons (v2-v10) into the extracellular part of the 90kDa constant form molecule
• Compared to the standard CD44, all larger isoforms are expressed in a much more restricted fashion, only in a few normal tissues or on the surface of certain tumor cells
• CD44 cell surface antigen is a 100 kDa type 1 transmembrane glycoprotein widely expressed on human leucocytes, white matter of the brain and by some epithelial cells of the intestine and breast
• Several isoforms of CD44 exist, including the predominant CD44H isoform detected in many normal tissues
• CD44 is a receptor for hyaluronic acid (HA) and is involved in cell-cell interactions, cell adhesion and migration
• CD44 also participates in a wide variety of cellular functions including lymphocyte activation, recirculation and homing
• CD44 expression may be up-regulated upon some carcinomas, and it has been speculated that this may be related to metastatic potential
• CD44 is expressed by hematopoietic, non-hematopoietic cells, epithelial tissues, and to filopodia in cultured keratinocytes
• Further, bone marrow myeloid cells and memory T cells express CD44 at high levels, and peripheral B and T cells can upregulate the expression of CD44 in response to certain stimulatory events
• Transcripts for the CD44 gene undergo complex alternative splicing that results in many functionally distinct isoforms, however, the full-length nature of some of these variants have not been determined
• Alternative splicing is the basis for the structural and functional diversity of the CD44 protein
• Diseases associated with CD44 dysfunction include superficial keratitis and lichen sclerosus
• CD44 also may be related to tumor metastasis formation.