General description
CD44 antigen (UniProt: P16070; also known as CDw44, Epican, Extracellular matrix receptor III, ECMR-III, GP90 lymphocyte homing/adhesion receptor, HUTCH-I, Heparan sulfate proteoglycan, Hermes antigen, Hyaluronate receptor, Phagocytic glycoprotein 1, PGP-1, CD44) is encoded by the CD44 (also known as LHR, MDU2, MDU3, MIC4) gene (Gene ID: 960) in human. CD44 is a single-pass type I, highly glycosylated membrane protein that is synthesized with a signal peptide (aa 1-20), which is subsequently cleaved off to generate the mature form that contains an extracellular domain (aa 21-649), a transmembrane domain (aa 650-670), and a cytoplasmic domain (aa 671-742). Nineteen different isoforms of CD44 have been described that are produced by alternative splicing. All isoforms possess a hyaluronic acid (HA)-binding domain in its N-terminal region in the extracellular domain. CD44 expression is observed on all leukocytes, endothelial cells, hepatocytes, and mesenchymal cells. It binds to several ligands including hyaluronic acid (HA), Osteopontin, chondroitin, collagen, fibronectin, and serglycin/sulfated proteoglycan. However, the main ligand for CD44 is HA that is expressed by stromal and cancer cells. HA binds the CD44 ligand binding domain and induces conformational changes that allow binding of adaptor proteins or cytoskeletal elements to intracellular domains. This leads to the activation of various signaling pathways leading to cell proliferation, adhesion, migration, and invasion. Overexpression of CD44 has been reported in several cell types and it is considered as an ideal marker for cancer stem cells. Its interaction with appropriate extracellular matrix ligands promotes the migration and invasion processes involved in tumor metastases. (Ref.: Chen, C., et al. (2018). J. Hematol. Oncol. 11; Article 64; Picker, LJ., et al. (1989). J. Cell Biol. 109(2); 927-937; Jalkanen, S., et al. (1987). J. Cell Biol. 105(2); 983-990).
Immunogen
Purified Hermes-1 antigen from KCA, a human B lymphoblastoid line.
Application
Quality Control Testing
Evaluated by Western Blotting in Human fetal foreskin tissue lysate.
Western Blotting Analysis: A 1:500 dilution of this antibody detected CD44 in Human fetal foreskin tissue lysate.
Tested Applications
Western Blotting Analysis: A 1:500 dilution from a representative lot detected CD44 in human tonsil tissue extracts.
ELISA Analysis: A representative lot detected CD44 in ELISA applications (Torrado, E., et al. (2013). PLoS One. 8(4):e61681).
Immunocytochemistry Analysis: A representative lot detected CD44 in Immunocytometry applications (Picker, L.J., et al. (1989). J Cell Biol. 109(2):927-37).
Flow Cytometry Analysis: A representative lot detected CD44 in Flow Cytometry applications (Jalkanen, S., et al. (1987). J Cell Biol. 105(2):983-90; Zhang, N., et al. (2012). Nat Immunol. 13(7):667-73).
Inhibition Assay: A representative lot selectively inhibited lymphocyte binding to lymph node and mucosal high endothelial venules. (Jalkanen, S., et al. (1987). J Cell Biol. 105(2):983-90).
Immunohistochemistry Applications: A representative lot detected CD44 in Immunohistochemistry applications (Huang, Z., et al. (2014). J Immunol.;192(11):5285-95).
Western Blotting Analysis: A representative lot detected CD44 in Western Blotting applications (Picker, L.J., et al. (1989). J Immunol. 142(6):2046-51; Picker, L.J., et al. (1989). J Cell Biol. 109(2):927-37).
Immunofluorescence Analysis: A representative lot detected CD44 in Immunofluorescence applications (Huang, Z., et al. (2014). J Immunol.; 92(11):5285-95).
Immunoprecipitation Analysis: A representative lot detected CD44 in Immunoprecipitation applications (Jalkanen, S., et al. (1987). J Cell Biol. 105(2):983-90).
Note: Actual optimal working dilutions must be determined by end user as specimens, and experimental conditions may vary with the end user.
Biochem/physiol Actions
Clone HERMES-3 is a mouse monoclonal antibody that detects CD44.
Physical form
Purified mouse monoclonal antibody IgG2a in PBS without preservatives.
Preparation Note
0.5 mg/mL. Please refer to guidance on suggested starting dilutions and/or titers per application and sample type.
Store at -10°C to -25°C. Handling Recommendations: Upon receipt and prior to removing the cap, centrifuge the vial and gently mix the solution. Aliquot into microcentrifuge tubes and store at -20°C. Avoid repeated freeze/thaw cycles, which may damage IgG and affect product performance.
Other Notes
Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.
Disclaimer
Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.
