TM4SF20 Antibody, FITC conjugated
Description
Antigen Target
TM4SF20 is a 21–25 kDa protein expressed in cancer cells, including stomach, lung, pancreatic, and colon cancers, with limited expression in normal tissues . The protein belongs to the L6 tetraspanin family and contains four transmembrane domains, with a large extracellular loop between transmembrane domains 3 and 4 .
Conjugation Methods and FITC Labeling
FITC conjugation involves covalently linking fluorescein isothiocyanate to the antibody’s lysine residues or amine groups. This process enhances detection in fluorescence microscopy and flow cytometry.
Key Parameters for FITC Conjugation
Critical Note: Higher FITC labeling indices reduce binding affinity due to steric hindrance, necessitating optimization for specific applications .
Experimental Uses
Therapeutic Potential:
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ADCC/CDC Activity: Monoclonal anti-TM4SF20 antibodies induce antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) in cancer cells .
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Bispecific Antibodies: Engineered variants bind TM4SF20 and cytotoxic agents (e.g., chemotherapeutics, radioactive isotopes) for targeted delivery .
Performance Characteristics
Critical Challenges:
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Heterogeneity: Polyclonal antibodies may exhibit variable epitope recognition compared to monoclonal alternatives .
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Non-Specific Staining: FITC-labeled antibodies with high labeling indices increase background noise in IHC/IF .
Product Comparison
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Ceramide alters the membrane orientation of TM4SF20, leading to a form that promotes the cleavage of CREB3L1. PMID: 27499293
- TM4SF20 is the first protein identified to undergo Regulated Alternative Translocation in response to ceramide. In the absence of ceramide, the N-terminus of the first transmembrane helix of TM4SF20 is inserted into the ER lumen. This configuration inhibits activation of CREB3L1, a membrane-bound transcription factor. Conversely, in the presence of ceramide, the membrane topology of TM4SF20 is inverted. This inverted form stimulates CREB3L1 cleavage. PMID: 27499293
- Ancestral deletions in the TM4SF20 gene are associated with a pediatric disorder characterized by early language delay and cerebral white matter hyperintensities. PMID: 23810381
