GB210 Antibody
Description
Definition and Biological Role of gp210 Antibody
gp210 is a 209 kDa transmembrane glycoprotein located in the nuclear pore complex . Anti-gp210 IgG antibodies are disease-specific antinuclear antibodies (ANAs) that serve as biomarkers for PBC, particularly in patients negative for antimitochondrial antibodies (AMA) . These antibodies are highly specific (>98%) but exhibit low sensitivity (~25%) for PBC .
Diagnostic Relevance
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AMA-Negative PBC: Anti-gp210 antibodies aid in diagnosing PBC in ~30% of AMA-negative patients .
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Diagnostic Criteria: The presence of anti-gp210 antibodies, alongside elevated alkaline phosphatase (ALP) and histologic evidence, confirms PBC .
Table 1: Diagnostic Thresholds for Anti-gp210 Antibody
| Anti-gp210 IgG Level (Units) | Interpretation |
|---|---|
| ≤20.1 | Negative |
| 20.1–24.9 | Equivocal |
| ≥25.0 | Positive |
Prognostic Value
Anti-gp210 positivity correlates with aggressive disease progression and poor outcomes:
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Mortality: 2.38-fold increased risk of death or liver transplantation .
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Treatment Response: 39.3% of anti-gp210-positive patients fail ursodeoxycholic acid (UDCA) therapy vs. 16.7% in negative cohorts .
Table 2: Prognostic Outcomes in Anti-gp210-Positive PBC
| Parameter | Anti-gp210 (+) | Anti-gp210 (−) |
|---|---|---|
| 5-Year Transplant-Free Survival | 77.0% | 90.3% |
| Liver-Related Mortality | 22.0% | 9.2% |
| Histologic Severity* | Higher | Lower |
*Includes lobular inflammation, interfacial hepatitis, and bile duct injury .
Mechanistic Insights
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Pathogenesis: Molecular mimicry triggered by bacterial or endogenous peptides may drive anti-gp210 production .
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Immune Response: T cells and cytokines (e.g., IL-12, IFN-γ) contribute to gp210 antigen presentation and antibody generation .
Diagnostic Methodology
Anti-gp210 antibodies are detected via semi-quantitative ELISA, with results reported in 1–8 days . Notably, HEp-2 indirect immunofluorescence (IFA) is unreliable for gp210 detection, necessitating confirmatory immunoassays .
Research Gaps and Future Directions
Product Specs
Composition: 50% Glycerol, 0.01M Phosphate Buffered Saline (PBS), pH 7.4
