ACS6 Antibody
Description
Overview of CS6 Antibody
CS6 antibodies target the CS6 antigen, a colonization factor expressed by Enterotoxigenic Escherichia coli (ETEC), a leading cause of diarrheal disease globally . These antibodies play a critical role in blocking bacterial adhesion to intestinal epithelial cells, preventing infection . CS6 is a heteropolymer composed of two subunits, CssA and CssB, which mediate ETEC binding to host cells .
Antibody Structure
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Fab Fragment: Binds to CS6 antigens via variable domains of heavy (V<sub>H</sub>) and light (V<sub>L</sub>) chains .
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Fc Region: Mediates immune effector functions (e.g., phagocytosis) .
CS6 Antigen Properties
Immunogenicity in Vaccine Trials
Intramuscular administration of CS6-based vaccines (e.g., CssBA + dmLT adjuvant) induced robust immune responses:
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Serum IgG/IgA: Peak titers observed on Day 71 post-vaccination .
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Mucosal Immunity: Anti-CS6 IgA antibodies detected in lymphocyte supernatants .
Prophylactic Efficacy in Human Trials
A randomized trial testing oral bovine anti-CS6 immunoglobulins (BSIgG) showed:
| Group | Moderate-Severe Diarrhea Rate | Efficacy vs Placebo |
|---|---|---|
| Placebo (n=20) | 70% (14/20) | — |
| Anti-CS6 BSIgG | 63% (12/19) | 10% (NS) |
| Anti-B7A BSIgG | 35% (7/20) | 50% (p=0.06) |
NS: Not statistically significant. Lack of efficacy for CS6-specific antibodies correlated with low CS6 surface expression on the challenge strain .
Molecular Detection of CS6 in ETEC Strains
PCR-based screening of ETEC isolates revealed:
CS6 was frequently co-expressed with other colonization factors (e.g., CS4, CS5) .
Therapeutic Potential
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Vaccine Development: CS6 is a candidate for multivalent ETEC vaccines due to its prevalence in endemic regions .
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Passive Immunization: Bovine-derived anti-CS6 antibodies showed safety but limited efficacy in human trials .
Limitations
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Antigen Variability: CS6 surface expression levels impact antibody efficacy .
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Adjuvant Dependency: Immune responses require potent adjuvants like dmLT .
Future Directions
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- ACS2 and ACS6 are the primary isoforms involved in cadmium-induced ethylene production. PMID: 25082369
- Protein phosphatase 2A inhibition stabilizes ACS6 protein. PMID: 21533019
- ACS2 and ACS6 participate in ethylene production induced by Botrytis. PMID: 20659280
- Studies indicate that the expression of ACS6 is upregulated during hypoxic conditions. PMID: 16028113
- Research has demonstrated that unphosphorylated ACS6 protein undergoes rapid degradation through the 26S proteasome pathway; the implications of this system on ethylene biosynthesis are discussed. PMID: 18182027
