ESCAPE-seq — A Massively Parallel Antigen-Presentation Discovery Platform

Why Antigen Discovery Needs Reinvention

HLA class I molecules are among the most polymorphic regions of the human genome. Mapping the peptides they present is central to understanding immune recognition, yet current tools leave critical gaps.

• Mass spectrometry requires large amounts of material and struggles with low-abundance or allele-specific peptides.
• Prediction algorithms are biased toward well-characterized alleles and often misclassify true binders, especially for underrepresented HLA types such as HLA-C.
• Coverage remains incomplete, limiting reliable immunopeptidome discovery across diverse populations.

ESCAPE-seq changes this landscape by combining single-chain trimer design, barcode-enabled libraries, and sequencing readouts. The result is a scalable and sensitive platform that directly measures peptide–HLA presentation, overcoming the bottlenecks of traditional methods.

ESCAPE-seq at a Glance — The Science Behind the Platform

In practice, this means: ESCAPE-seq turns antigen discovery into a scalable sequencing problem, providing researchers with a direct, quantitative, and parallel view of how peptides interact with diverse HLA alleles.

Core Advantages for Your Research

ESCAPE-seq is designed to overcome the bottlenecks that limit conventional antigen discovery methods. By combining synthetic trimer design, surface-display biology, and sequencing-based quantification, it offers a powerful set of benefits for research teams.

• Massively Parallel Screening
  Evaluate tens of thousands of peptide–HLA combinations in a single experiment, making large-scale immunopeptidome analysis practical and reproducible.
• High Sensitivity for Rare Events
  Capture low-abundance and mutation-derived peptides that traditional mass spectrometry or algorithms often miss, including those restricted by HLA-C alleles.
• Beyond Mass Spectrometry
  Remove the heavy sample requirements and allele ambiguity of MS-based approaches with a direct, scalable sequencing workflow.
• Broad HLA Coverage
  Achieve population-wide insight by profiling diverse HLA-A, HLA-B, and HLA-C variants, reducing allele bias in antigen discovery.
• Quantitative & Comparable Data
  Generate standardized E-scores that allow you to compare peptide presentation strength across alleles, mutations, and peptide libraries.

In short: ESCAPE-seq provides a high-throughput, unbiased, and sensitive solution for peptide–HLA interaction research, enabling you to see the full landscape of antigen presentation with clarity and confidence.

Technical Deep Dive — Beyond Prediction and MS

ESCAPE-seq takes antigen discovery further than prediction models and mass spectrometry. Instead of relying on indirect inference, it directly measures peptide–HLA presentation at scale.

Our Service Workflow — From Design to Discovery

We structure our ESCAPE-seq service as a clear, step-by-step process, so you know exactly how your project moves from idea to data delivery.

Bioinformatics Analysis — Data That Drives Insight

The strength of ESCAPE-seq lies not only in the experimental workflow but also in how the results are processed and interpreted. Our bioinformatics pipeline transforms sequencing output into structured, research-ready insight.

Data Quality and Normalization

• Rigorous quality control of sequencing reads and barcode counts
• Normalization to ensure comparability across alleles, libraries, and replicates

E-score Matrix Generation

• Quantitative ranking of peptide–HLA presentation strength
• Scalable matrices that allow side-by-side comparison of thousands of interactions

Comparative Epitope Profiling

• Mutation vs. wild-type analysis to reveal differential presentation patterns
• Identification of mutation-only epitopes most likely to shape immune recognition
• Detection of public neoantigens displayed across multiple HLA alleles

Population-Level Coverage

• Integration of results across HLA-A, HLA-B, and HLA-C alleles
• Assessment of allele-specific biases and breadth of coverage

Visualization and Reporting

• Heatmaps, scatterplots, and ranked epitope lists for intuitive data interpretation
• Exportable datasets for downstream integration with other omics or immunological studies

Final Deliverables

Upon completion of the ESCAPE-seq analysis, you will receive:

Sample Requirements

To ensure data quality and reproducibility, please prepare your samples or sequence information according to the following guidelines:

Peptide or DNA Input

• Provide peptide libraries in sequence format (FASTA/CSV) or DNA constructs designed for expression.
• Custom peptide sequences should be validated for accuracy prior to submission.

HLA Information

• Indicate the specific HLA alleles of interest (HLA-A, HLA-B, HLA-C).
• Reference allele IDs should follow standard nomenclature (e.g., HLA-A*02:01).

Cell Lines (if applicable)

• If project-specific cell lines are required, provide cells with stable growth characteristics.
• Confirm absence of mycoplasma or contamination.

Sample Integrity

• Ensure DNA or peptide libraries are free of contaminants (e.g., salts, proteins, residual solvents).
• Recommended OD260/280 values ~1.8–2.0 for nucleic acids.

Storage & Shipping

• DNA libraries: ship on dry ice or cold packs.
• Peptide libraries: ship lyophilized or in low-salt buffer, stable at -20°C or below.
• Provide detailed documentation of storage conditions.

Applications — Where ESCAPE-seq Makes a Difference

ESCAPE-seq is not just a new assay—it is a versatile platform that opens up research possibilities across multiple areas of immunology.

Case Study

Title: Massively parallel immunopeptidome by DNA sequencing provides insights into cancer antigen presentation

Journal: Nature Genetics

Method: ESCAPE-seq (Massively Parallel Antigen-Presentation Sequencing)

Authors: Quanming Shi, Elana P. Simon, Howard Y. Chang et al.

Summary:

Using ESCAPE‑seq to screen over 75,000 peptide–HLA class I combinations, researchers uncovered a rich spectrum of antigen presentation. This includes broadly presented epitopes derived from oncogenic driver mutations and fusion proteins across diverse HLA‑A, HLA‑B, and HLA‑C alleles—covering approximately 90% of the population. Differential analysis between mutant and wild‑type peptides revealed distinct presentation patterns. Notably, some mutation‑specific peptides (such as EGFR(T790M) and MED12(G44V)) were presented by over 60% of tested HLA alleles (“public neoantigens”), while other epitopes were uniquely presented in the mutated form (WT⁻ / Mut⁺). Functional validation confirmed that these mutation‑only epitopes induced robust IFN‑γ⁺ TNF‑α⁺ CD8⁺ T cell responses, confirming their immunological relevance.

ESCAPE-seq reveals presented peptides in SARS-CoV-2 spike and nucleocapsid proteins, and strain variants.

ESCAPE-seq Service FAQs — Common Questions Answered

• What makes ESCAPE-seq different from traditional antigen discovery methods?
  • • ESCAPE-seq directly measures peptide–HLA complex formation via sequencing, instead of inferring from computational models or extracting via mass spectrometry.
    • It scales across tens of thousands of combinations in a single run, capturing rare and allele-specific presentations that often evade other methods.
• Can ESCAPE-seq handle uncommon HLA alleles?
  • • Yes—unlike prediction tools that rely on training data, ESCAPE-seq empirically tests each peptide–HLA combination. Even alleles with sparse historical data (e.g., certain HLA-C variants) are assessed directly.
• Is mass spectrometry required at any stage?
  • • No. ESCAPE-seq bypasses mass spectrometry entirely. It uses cell-surface trafficking of single-chain trimers (SCTs) and barcode sequencing for quantitative measurement, reducing sample demands and simplifying workflow.
• How quantitative are the results?
  • • Results are given as E-scores, continuous metrics that reflect relative presentation strength. You receive ranked tables and visual heatmaps, allowing for direct comparison across mutations, alleles, and peptide libraries.
• How customizable is the assay?
  • • Very flexible. You define the peptide library and HLA alleles of interest during the consultation phase. Libraries can include mutated sequences, fusion peptides, or any novel targets you wish to explore.
• What does the turnaround look like?
  • • Typically, projects follow a structured pipeline—consultation, library construction, sorting, sequencing, and analysis. While exact timing depends on library scope, we will outline an expected timeline during project planning for clarity and coordination.