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Biology subjects

Egorov, E. S.

Publications and source records attributed to Egorov, E. S..

3 recordsLinked to original sources

Discovery of rare antigen-specific TCRs via replicate profiling

Development of effective vaccines and targeted immunotherapies for cancer, autoimmunity, allergy, and infectious diseases requires comprehensive understanding of functionality and antigenic specificity of involved T cell clones. A major technical challenge remains the high-throughput identification of antigen-specific T cells. Here, we present a rapid cost-efficient TCR discovery assay starting from PBMC that enables ultra-sensitive discovery of clonal alpha-beta paired TCRs responding to individual or pooled peptides. In a small-scale experiment with a single donor, assay identified over 90 SARS-CoV-2-specific CD4+ and CD8+ TCR{beta} clonotypes, validated by clonal tracking and comparison against known SARS-CoV-2-specific TCRs. Positioning within the scRNA-Seq map revealed distinct helper T cell subsets involved in primary and secondary response. Further validation in a cohort of five donors identified nearly 1,000 CD4+ and CD8+ TCR clonotypes specific to viral and fungal peptide antigens. The assay demonstrated exceptional sensitivity in capturing low-frequency clones and allowed accurate TCR/TCR{beta} pairing, validated using single-cell transcriptomics. The ability to capture low-frequency antigen-specific TCRs, combined with detailed scRNA-Seq annotation, establishes an integrated pipeline that links antigen-responsive clones to their precise functional phenotypes. This platform provides a robust foundation for dissecting T cell roles in health and disease and accelerates the development of vaccines and immunotherapies.

immunology↗

Splicing-aware resolution of scRNA-Seq data

Single-cell RNA sequencing (scRNA-Seq) provides invaluable insights in cell biology. Current scRNA-Seq analytic approaches do not distinguish between spliced and unspliced mRNA. RNA velocity paradigm suggests that the presence of unspliced mRNA reflects transitional cell states, informative for studies of dynamic processes such as embryogenesis or tissue regeneration. Alternatively, stable cell subsets may also maintain unspliced mRNA reservoirs for prompt initiation of transcription-independent expression. Based on the latter paradigm, we have developed a method called SANSARA (Splicing-Aware scrNa-Seq AppRoAch) for the splicing-aware analysis of scRNA-Seq data. We employed SANSARA to characterize peripheral blood regulatory T cell (Treg) subsets, revealing the complex interplay between FoxP3 and Helios master transcription factors and other unexpected splicing-informed features. For Th1 and cytotoxic CD4+ T cell subsets, SANSARA also revealed substantial splicing heterogeneity across crucial subset-specific genes. SANSARA is straightforward to implement in current data analysis pipelines and opens new dimensions in scRNA-Seq-based discoveries.

immunology↗

Precise tracking of vaccine-responding T-cell clones reveals convergent and personalized response in identical twins

T-cell receptor (TCR) repertoire data contain information about infections that could be used in disease diagnostics and vaccine development, but extracting that information remains a major challenge. Here we developed a statistical framework to detect TCR clone proliferation and contraction from longitudinal repertoire data. We applied this framework to data from three pairs of identical twins immunized with the yellow fever vaccine. We identified 500-1500 responding TCRs in each donor and validated them using three independent assays. While the responding TCRs were mostly private, albeit with higher overlap between twins, they could be well predicted using a classifier based on sequence similarity. Our method can also be applied to samples obtained post-infection, making it suitable for systematic discovery of new infection-specific TCRs in the clinic.

immunology↗