Biased TCR gene usage in citrullinated Tenascin C specific T-cells in rheumatoid arthritis

Abstract

We aimed to search for common features in the autoreactive T cell receptor (TCR) repertoire in patients with rheumatoid arthritis (RA), focusing on the newly identified candidate antigen citrullinated Tenascin C (cit-TNC). Mononuclear cells from peripheral blood or synovial fluid of eight RA-patients positive for the RA-associated HLA-DRB1*04:01 allele were in-vitro cultured with recently identified citrullinated peptides from Tenascin C. Antigen-specific T cells were isolated using peptide-HLA tetramer staining and subsequently single-cell sequenced for paired alpha/beta TCR analyses by bioinformatic tools. TCRs were re-expressed for further studies of antigen-specificity and T cell responses. Autoreactive T cell lines could be grown out from both peripheral blood and synovial fluid. We demonstrate the feasibility of retrieving true autoreactive TCR sequences by validating antigen-specificity in T cell lines with re-expressed TCRs. One of the Tenascin C peptides, cit-TNC22, gave the most robust T cell responses including biased TCR gene usage patterns. The shared TCR-beta chain signature among the cit-TNC22-specific TCRs was evident in blood and synovial fluid of different patients. The identification of common elements in the autoreactive TCR repertoire gives promise to the possibility of both immune monitoring of the autoimmune components in RA and of future antigen- or TCR-targeted specific intervention in subsets of patients.

Diversity and Clonality of T Cell Receptor Repertoire and Antigen Specificities in Small Joints of Early Rheumatoid Arthritis

“…In support of the observed TRBV20-1 bias, we have recently demonstrated a skewing of this gene segment in antigen-specific T cells recognizing citrullinated tenascin-C in peripheral blood and synovial fluid from RA patients with established disease (39). Importantly, it has also previously been shown that variable gene usage is in part influenced by HLA type (40), which might also contribute to our findings.…”

Autoreactive CD8 T cells in NOD mice exhibit phenotypic heterogeneity but restricted TCR gene usage

“…These novel findings therefore demonstrate that TCR gene usage in IGRP 206-214 –reactive CD8 T cells is even more restricted than previously thought. Evidence of restricted TCR gene usage in IGRP 206-214 –reactive CD8 T cells may also warrant the investigation of TCR gene usage in T cells reactive to other commonly targeted β cell epitopes, such as insulin ( Amdare et al, 2021 ), at the single-cell level; these data parallel findings of restricted TCR repertoires among autoreactive T cells found in other autoimmune disorders such as experimental autoimmune encephalomyelitis ( Acha-Orbea et al, 1988 ; Urban et al, 1988 ; Sakai et al, 1989 ), polymyositis ( Mantegazza et al, 1993 ), rheumatoid arthritis ( Williams et al, 1992 ; Sharma et al, 2021 ), thyroiditis ( Martin et al, 1999 ), and primary biliary cirrhosis ( Moebius et al, 1990 ). It would also be valuable to apply scTCR-seq to CD8 T cells targeting other autoantigens in the islets of NOD mice to see if this trend holds for CD8 T cells targeting other antigens; although we studied IGRP 206-214 –nonreactive CD8 T cells in bulk in this study, we did not separately sort and sequence CD8 T cells targeting specific autoantigens other than IGRP 206-214 because of technical limitations of cell recovery.…”

Single-cell characterisation of tissue homing CD4 + and CD8 + T cell clones in immune-mediated refractory arthritis

“…3 f). Using GLIPH2 (Sharma et al 2021 ), we used publicly available data from a cohort of JIA patients, as reported by Henderson et al (Henderson et al 2016 ), to check TCR level similarity between the two cohorts. All patterns found in the healthy samples and Lyme disease patients were removed to retain possible RA associated motifs only.…”