Biology subjects

Tiffeau-Mayer, A.

Publications and source records attributed to Tiffeau-Mayer, A..

2 recordsLinked to original sources

bioRxiv2024

Tissue determinants of the human T cell receptor repertoire.

98% of T cells reside in tissues, yet nearly all human T cell analyses are performed from peripheral blood. We single-cell sequenced 5.7 million T cells from ten donors autologous blood and tonsils and sought to answer key questions about T cell receptor biology previously unanswerable by smaller-scale experiments. We identified distinct clonal expansions and distributions in blood compared to tonsils, with surprisingly low (1-7%) clonal sharing. These few shared clones exhibited divergent phenotypes across bodily sites. Analysis of antigen-specific CD8 T cells revealed location as a main determinant of frequency, phenotype, and immunodominance. Finally, diversity estimates from the tissue recalibrates current repertoire diversity estimates, and we provide a refined estimate of whole-body repertoire. Given the tissue-restricted nature of T cell phenotypes, functions, differentiation, and clonality revealed by this dataset, we conclude that tissue analyses are crucial for accurate repertoire analysis and monitoring changes after perturbing therapies.

immunology↗

bioRxiv2024

Intra- and inter-chain contacts determine TCR specificity: applying protein co-evolution methods to TCRαβ pairing

The six complementarity determining regions (CDRs) of the T cell receptor (TCR) form multiple contacts with cognate peptide and major histocompatibility complex, thus determining antigen specificity. However, the contacts between the CDRs themselves are less understood. We perform a systematic study of all available TCR structures, and identify consistent patterns of intra- and inter-chain CDR contacts. We further show that the sequences of paired TCR and TCR{beta} are not independent within sets of antigen-specific TCRs, for most epitopes. We quantify this sequence restriction using a mutual information framework. Co-evolution models can achieve some de novo prediction of TCR/TCR{beta} pairing, without using a training set of known pairs. The conserved pattern of CDR amino acid contacts, and the mutual sequence constraints between antigen-specific sets of T cell receptor and {beta} chains could play an important role in shaping the antigen-specific T cell repertoire.

immunology↗