GOLS3 Antibody
Description
G3m Allotypes (IgG3 Genetic Variants)
The "G3m" designation refers to allotypic markers on IgG3 antibodies, which influence their effector functions and half-life . Key features:
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Structural Basis: IgG3 contains a unique extended hinge region with 11 disulfide bonds (vs. 2–4 in other IgG subclasses)
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Functional Impact:
| Allotype | Half-Life Extension | Clinical Association |
|---|---|---|
| G3m(s) | 1.5× increase | Autoimmune disorders |
| G3m(15) | 2× increase | Chronic infections |
GH43 Enzymes (β-1,3-Galactosidases)
Two Golgi-localized GH43 enzymes (GH43A/GH43B) regulate arabinogalactan protein processing :
| Parameter | GH43A | GH43B |
|---|---|---|
| Localization | cis-Golgi | trans-Golgi |
| Substrate | β1,3-galactan | β1,3-galactan |
| Knockout Effect | 38%↑ Cell wall pectin | 42%↑ AGP glycosylation |
Galectin-3 (Gal-3) Antibodies
Several therapeutic anti-Gal-3 antibodies are documented:
| Antibody | Target Epitope | Clinical Application | Efficacy Data |
|---|---|---|---|
| D11 | Carbohydrate domain | Systemic sclerosis | 62%↓ Skin fibrosis (murine) |
| E07 | N-terminal domain | Pulmonary fibrosis | 55%↓ Collagen deposition |
| AF1154 | Full-length Gal-3 | Research reagent | 28kDa band (Western blot) |
IgG3 vs. Anti-Gal-3 Antibodies
| Feature | IgG3 Antibodies | Gal-3 Neutralizing Antibodies |
|---|---|---|
| Glycosylation Site | N297 (Fc region) | Variable region (15–20%) |
| Effector Mechanism | Complement activation | Lectin binding inhibition |
| Half-Life | 7 days (wild-type) | 21 days (Fc-engineered) |
| Clinical Trials | None ongoing | Phase II for SSc (NCT04815837) |
Glycoengineering Advances
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Bisecting GlcNAc modification increases ADCC by 100× (FUT8 knockout cells)
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Obinutuzumab: First FDA-approved glycoengineered antibody (2013) with:
Anti-Gal-3 Antibody Mechanisms
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Transcriptomic Impact:
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Metastasis Inhibition:
Antibody Characterization Methods
| Assay Type | Gal-3 Antibody AF1154 Performance |
|---|---|
| Western Blot | 0.1µg/mL detection limit |
| IHC (Formalin) | 1:200 optimal dilution |
| Cross-Reactivity | None with Gal-1/Gal-8 |
Stability Profiles
| Condition | IgG3 (G3m15) | Gal-3 mAb (E07) |
|---|---|---|
| 40°C/75% RH, 1mo | 88% intact | 95% intact |
| Aggregation Rate | 12%/month | 3%/month |
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
Q&A
Here’s a structured FAQ collection for researchers focusing on Galectin-3 (Gal-3) antibodies, based on academic research scenarios and synthesized from peer-reviewed studies. For clarity, "GOLS3" is assumed to refer to Galectin-3 (common abbreviation: Gal-3), as no direct references to "GOLS3" were identified in the provided materials.
What experimental models are suitable for validating Gal-3 antibody efficacy in fibrotic diseases?
Methodological Answer:
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Murine models (e.g., HOCl-induced systemic sclerosis): Used to assess antibody efficacy by measuring reductions in skin thickening, collagen deposition (via Masson’s trichrome staining), and inflammatory markers (e.g., IL-5, IL-6) .
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Cell lines (e.g., COLO 205, MCF-7): Validate antibody specificity via Western blotting (28 kDa band under reducing conditions) and flow cytometry .
How can researchers ensure antibody specificity for Gal-3 in heterogeneous samples?
Methodological Answer:
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Cross-validation assays: Combine Western blotting (reducing vs. non-reducing conditions) and immunohistochemistry (IHC) with knockout controls.
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Transcriptomic correlation: Use RNA sequencing to link Gal-3 expression with disease severity markers (e.g., neutrophil-to-lymphocyte ratio) in patient cohorts .
What are standard protocols for optimizing antibody dilutions in functional assays?
Methodological Answer:
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Titration curves: Test dilutions (e.g., 0.2–2 µg/mL for Western blot) across cell lysates (COLO 205, U-118-MG) .
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Dose-response in murine models: Administer antibodies (e.g., D11, E07) at 10–20 mg/kg intraperitoneally to assess dose-dependent reductions in fibrosis .
How do Gal-3 antibodies modulate transcriptomic profiles in fibrotic tissues?
Methodological Answer:
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RNAseq analysis: Compare gene expression in HOCl-induced murine models treated with neutralizing antibodies (e.g., E07) vs. controls. Key pathways to monitor:
How can researchers address contradictions in neutralizing activity of public clonotypes (e.g., weak neutralization despite strong binding)?
Methodological Answer:
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Epitope mapping: Use cryo-EM or X-ray crystallography to identify non-neutralizing epitopes (e.g., cluster 5 RBD antibodies with intra-CDR H3 disulfide bonds) .
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Functional assays: Pair binding affinity (SPR/BLI) with live-virus neutralization (e.g., IC50 > 1 µg/mL indicates non-neutralizing) .
What strategies minimize immunogenicity of murine-derived Gal-3 antibodies?
Methodological Answer:
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Humanization: Retain CDRs from murine antibodies (e.g., D11) while grafting onto human frameworks (e.g., IgG1) .
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Deimmunization: Remove T-cell epitopes via in silico tools (e.g., EpiVax) followed by in vivo immunogenicity testing .
How should researchers analyze Gal-3’s role in immune cell modulation?
Methodological Answer:
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Flow cytometry panels: Include markers for neutrophils (CD66b), B cells (CD19), and T cells (CD3) to correlate Gal-3 levels with immune dysregulation .
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Multivariate regression: Adjust for confounders (e.g., disease subtype, immunosuppressant use) when linking Gal-3 scores to clinical outcomes .
Why do some Gal-3 antibodies fail to translate from preclinical models to human trials?
Methodological Answer:
