Biology subjects

Piekarsa, V.

Publications and source records attributed to Piekarsa, V..

2 recordsLinked to original sources

bioRxiv2026

The αβTCR repertoire at scale in the immgenT dataset

The immense T cell receptor (TCR) repertoire is shaped by VDJ combinatorial diversity, imprecise rearrangements, and clonal selection. The immgenT Project generated scRNA and TCRseq to map paired {beta}TCR repertoires across 734 mouse samples from diverse tissues and challenge conditions. Compositional analysis uncovered some extreme junctional architectures. Beyond probabilistic V and J pairing, over-represented joins suggested non-randomness in fine joining, broadening the precedent of quasi-invariant iNKT and MAIT TCRs. We charted public clonotypes linked to self or environmental antigens in the main lineages. Tissue analyses revealed compartmentalized tissue-specific expansions. Unproductive and productive rearrangements of a V gene appeared to interfere specifically with each other, at chromatin or RNA levels. Unexpectedly, allelic exclusion at TCR{beta} proved less stringent than thought, and we identified rearrangements of TCR in immature pre-T stages. This organism-wide look into the TCR repertoire offers novel insights on the evolutionary and immunological pressures on TCR repertoire selection.

immunology↗

bioRxiv2024

Genomic Specificity of Anti-TCR mAbs determined by single-cell RNAseq

T cells play a pivotal role in the immune system, relying on their somatically rearranged T cell receptor (TCR) to recognize peptide-MHC complexes. A comprehensive and extensively used set of monoclonal antibodies (mAbs) against TCR Variable regions was generated in the previous century. The separate identification of mAb-specific TCR-V proteins and TRV genes has resulted in multiple nomenclatures, making their relationships unclear. To formally re-establish this link and determine patterns of reactivity within TRV subfamilies, we sorted T cells positive for any one of a panel of 22 anti-V mAbs and determined their TRV genes by single-cell TCRseq. RNAseq data revealed consistently higher expression of repeated elements from the ERV1-family LTR RLTR6Mm (mapping to Gm20400) in cells utilizing TRBV segments encoded within a 66kb genomic region between TRBV23 and TRBV30. Our findings provide a comprehensive resource for anti-TCR mAb specificity and insight into V-gene usage biases and T cell function.

immunology↗