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EpiVax HLA Binding Assay


EpiVax Methods

24 HOURS

Test peptide (predicted by EpiMatrix) Biotinylated high-affinity control peptide HLA class II monomer

Y Y Y Y YY Y Y Europium-labeled Streptavidin only targets biotinylated peptides

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Unbound peptide removed in wash step

Y Y YY YY Y Y High-absorbance ELISA capture plate

Fluorescence counts are converted into percent inhibition of biotinylated standard

PLATE READER (EU+)

Each test peptide is assayed at multiple concentrations If dose-dependence curves are observed, IC50 values are calculated using SigmaPlot software The lower the IC50 the higher the binding affinity of the test peptide


EpiVax Methods In-Depth

The plate is incubated overnight at 37Ëš

Biotinylated tracer peptide is added to each well on the plate Specific HLA allele is added to each well of the plate

Test peptides compete with biotinylated tracer peptides for binding on HLA molecules

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Test peptides


EpiVax Methods In-Depth The mixture of HLA, test peptides, and biotinylated control peptides is transferred into a 96-well plate coated with anti-HLA antibody

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Anti-HLA antibodies capture the HLApeptide complexes

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Europium-tagged Streptavidin is added to each well The Streptavidin binds to the biotinylated control peptide and releases its Europium tag, creating fluorescence


EpiVax Methods In-Depth Strong binder example When the mixture is transferred to a plate coated with anti-HLA antibody and Europiumlabeled Streptavidin is added, the Streptavidin only recognizes the biotinylated control peptide

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Only bound Streptavidin releases its Europium tag, leading to little or no fluorescence

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EpiVax Methods In-Depth Weak binder example When the mixture is transferred to a plate coated with anti-HLA antibody and Europiumlabeled Streptavidin is added, the Streptavidin only recognizes the biotinylated control peptide Only bound Streptavidin releases its Europium tag, leading to high fluorescence

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EpiVax HLA Coverage

EpiVax tests for binding to the most common HLA molecules within each of the “supertypes� shown to the left. This allows us to provide results that are representative of >90% of human populations worldwide without the necessity of testing each haplotype individually.

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EpiVax Sample Results

Above is an example of data obtained by testing at concentrations spanning several orders of magnitude. Darker colors indicate stronger binding. This approach is preferable to screening at a single concentration, since every peptide exhibits a unique dose response. Confidential


EpiVax Sample Results

The IC50 of a test peptide is the theoretical concentration at which half of the biotinylated control peptide binding is inhibited. Detailed plots of the titration curve and IC50 location are provided with each report, along with EpiMatrix comparison analysis. Confidential


EpiVax Sample Results

Strong binder

Moderate binder

Weak binder

The shape of each inhibition curve and the location of its intercept with 50% maximal binding dictates how a test peptide is characterized. EpiVax uses this information to delineate between strong, moderate and weak binders. Rating peptides by these criteria works in tandem with the detailed profile provided by displaying a representation of a peptide’s entire effective range.

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EpiVax HLA Binding Assay: Competitive Advantages

Supported by a comprehensive informatics suite Binding assay is robust and informative Backed by an extensive immunology knowledge base Flexibility in assay design and execution Troubleshooting and analysis of output

Thank you for considering EpiVax.

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HLA Binding Assays