LACS8 Antibody
Product Specs
**Constituents:** 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- LACS8 is expressed in a variety of organs and throughout embryonic development. Notably, overexpression of LACS8 in seeds does not influence fatty acid content. PMID: 21143684
Q&A
FAQ: Lassa Virus-Specific CD8+ T Cell Antibody Responses in Research Contexts
How are LASV-specific CD8+ T cell epitopes identified in survivors?
To identify epitopes, researchers use:
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Recombinant antigen libraries: Fragments of LASV glycoprotein (GPC) and nucleoprotein (NP) are expressed via recombinant vesicular stomatitis virus (rscVSV) systems to stimulate peripheral blood mononuclear cells (PBMCs) from survivors .
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HLA-binding algorithms: Predictive tools prioritize epitopes likely to bind HLA alleles common in survivor cohorts (e.g., Sierra Leonean and Nigerian populations) .
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Functional validation: Autologous survivor PBMCs are tested for cytokine production (IFN-γ, TNF-α) via intracellular staining after antigen stimulation .
What assays are used to measure LASV-specific CD8+ T cell responses?
Two primary methods are employed:
| Assay Type | Duration | Sensitivity | Use Case |
|---|---|---|---|
| 18-hour stimulation | Short-term | Low | Detects high-frequency circulating T cells . |
| 10-day proliferation | Long-term | High | Expands low-frequency memory T cells for detection . |
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The 10-day assay is critical for identifying durable immunity in survivors >10 years post-infection .
How are LASV antibody levels correlated with T cell responses?
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ELISA: Anti-GP and anti-NP antibody titers are quantified post-vaccination or infection. Survivors with CD8+ T cell responses show higher mean anti-GP (11.0 vs. 6.9) and anti-NP (35.6 vs. 29.7) levels compared to non-responders .
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Neutralization assays: Percent neutralization correlates weakly with T cell activity (51% in responders vs. 68% in non-responders) .
How to resolve discrepancies in CD8+ T cell response detection across studies?
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Issue: Some studies report undetectable responses using short-term assays .
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Solution:
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Expand precursor cells: Use 10-day proliferation assays to amplify low-frequency memory T cells .
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Multi-cytokine analysis: Measure TNF-α+IFN-γ+ co-expression to reduce background noise from single-cytokine assays .
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Longitudinal sampling: Track responses over time, as antibody and T cell levels decline post-infection (e.g., anti-GP/NP titers drop by ~50% after 20 years) .
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What strategies improve epitope conservation for pan-LASV vaccine design?
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Target selection: Prioritize epitopes from highly conserved regions of GPC and NP (e.g., GP2, sspGP2) .
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Cross-lineage validation: Test epitopes against multiple LASV lineages (e.g., lineage IV Josiah strain vs. Nigerian variants) .
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Structural modeling: Predict epitope-HLA binding stability using computational tools to ensure broad population coverage .
How to optimize flow cytometry panels for LASV-specific T cell studies?
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Marker selection: Include CD45 (leukocyte), CD3 (T cell), CD8 (cytotoxic), and cytokines (IFN-γ/TNF-α) .
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Gating strategy:
Why do some survivors lack detectable CD8+ T cell responses despite prior infection?
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Low precursor frequency: Memory T cells may decline to undetectable levels over time (e.g., <1% in survivors >10 years post-infection) .
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Assay limitations: Short-term assays fail to detect cells requiring reactivation.
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Solution: Combine 10-day expansion with antigen-specific stimulation (e.g., rscVSV-GP2) .
