Rescue of thymocytes and T cell hybridomas from glucocorticoid-induced apoptosis by stimulation via the T cell receptor/CD3 complex: a possiblein vitro model for positive selection of the T cell repertoire

1991 ◽  
Vol 21 (3) ◽  
pp. 643-648 ◽  
Author(s):  
M. Iwata ◽  
S. Hanaoka ◽  
Kazuki Sato
1992 ◽  
Vol 176 (2) ◽  
pp. 459-468 ◽  
Author(s):  
R Abe ◽  
Y Ishida ◽  
K Yui ◽  
M Katsumata ◽  
T M Chused

Shaping of the T cell repertoire by selection during intrathymic maturation involves T cell receptor (TCR) recognition of major histocompatibility complex/self-antigen complexes. In this communication, we studied the ability of minor lymphocyte stimulating (Mls) determinants to act as self-tolerogens in the selection of the T cell repertoire. We demonstrate that unprimed T cells from normal as well as TCR transgenic mice form Mls-specific conjugates with antigen-presenting cells, and that this TCR-ligand interaction leads to elevation of intercellular Ca2+ ([Ca2+]i). Peripheral T cells from TCR transgenic mice expressing receptors specific for self-Mls antigen show no reactivities to Mlsa. However, a proportion of immature thymocytes from these mice show specific binding and strong [Ca2+]i elevation in response to self-antigen-presenting cells, although these thymocytes do not proliferate. This self-reactivity of thymocytes is inhibited by antibodies specific for TCR, CD4, CD8, class II molecules, lymphocyte function-associated antigen 1, and intercellular adhesion molecule 1. These results demonstrate for the first time that before thymic negative selection, immature T cells can specifically interact with cells bearing self-antigen, and suggest that the resulting TCR-dependent signal transduction events provide a basis for negative selection of self-reactive T cells.


Nature ◽  
1995 ◽  
Vol 374 (6521) ◽  
pp. 474-476 ◽  
Author(s):  
Klaus-Dieter Fischer ◽  
Antanina Zmuidzinas ◽  
Sandra Gardner ◽  
Mariano Barbacid ◽  
Alan Bernstein ◽  
...  

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5186-5186
Author(s):  
Ronald M. Paranal ◽  
Hagop M. Kantarjian ◽  
Alexandre Reuben ◽  
Celine Kerros ◽  
Priya Koppikar ◽  
...  

Introduction: Allogeneic hematopoietic stem-cell transplantation (HSCT) is curative for many patients with advanced hematologic cancers, including adverse-risk acute myeloid leukemia (AML). This is principally through the induction of a graft-versus-leukemia (GVL) immune effect, mediated by donor T-cells. The incredible diversity and specificity of T-cells is due to rearrangement between V, D, and J regions and the random insertion/deletion of nucleotides, taking place in the hypervariable complementarity determining region 3 (CD3) of the T-cell receptor (TCR). Massively parallel sequencing of CDR3 allows for a detailed understanding of the T-cell repertoire, an area relatively unexplored in AML. Therefore, we sought out to characterize the T-cell repertoire in AML before and after HSCT, specifically for those with a durable remission. Methods: We identified 45 bone marrow biopsy samples, paired pre- and post-HSCT, from 14 patients with AML in remission for > 2 years as of last follow-up. We next performed immunosequencing of the TCRβ repertoire (Adaptive Biotechnologies). DNA was amplified in a bias-controlled multiplex PCR, resulting in amplification of rearranged VDJ segments, followed by high-throughput sequencing. Resultant sequences were collapsed and filtered in order to identify and quantitate the absolute abundance of each unique TCRβ CDR3 region. We next employed various metrics to characterize changes in the TCR repertoire: (1) clonality (range: 0-1; values closer to 1 indicate a more oligoclonal repertoire), it accounts for both the number of unique clonotypes and the extent to which a few clonotypes dominate the repertoire; (2) richness with a higher number indicating a more diverse repertoire with more unique rearrangements); (3) overlap (range: 0-1; with 1 being an identical T-cell repertoire). All calculations were done using the ImmunoSeq Analyzer software. Results: The median age of patients included in this cohort was 58 years (range: 31-69). Six patient (43%) had a matched related donor, and 8 (57%) had a matched unrelated donor. Baseline characteristics are summarized in Figure 1A. Six samples were excluded from further analysis due to quality. TCR richness did not differ comparing pre- and post-HSCT, with a median number pre-HSCT of 3566 unique sequences (range: 1282-22509) vs 3720 (range: 1540-12879) post-HSCT (P = 0.7). In order to assess whether there was expansion of certain T-cell clones following HSCT, we employed several metrics and all were indicative of an increase in clonality (Figure 2B). Productive clonality, a measure of reactivity, was significantly higher in post-transplant samples (0.09 vs 0.02, P = 0.003). This is a measure that would predict expansion of sequences likely to produce functional TCRs. The Maximum Productive Frequency Index was higher post-HSCT indicating that the increase in clonality was driven by the top clone (most prevalent per sample). Similarly for the Simpson's Dominance index, another marker of clonality which was higher post-HSCT (0.01 vs 0.0009, P = 0.04). In order to determine whether this clonal expansion was driven by TCR clones shared among patients, we compared the degree of overlap in unique sequences among pre and post-HSCT samples. We found there was very little overlap between samples in the pre and the post-transplant setting and no change in the Morisita and Jaccard Overlap Indices. Conclusions: In conclusion, we show in this analysis an increase in clonality of T-cells following HSCT in patients with AML. This is likely related to the GVL effect after recognition of leukemia antigens by donor T cells and subsequent expansion of these T-cells. These expanded T-cell clonotypes were unlikely to be shared by patients in this cohort, likely reflecting the variety of antigens leading to the GVL effect. This could have direct implications on TCR-mediated immune-therapies given the likely need for a personalized, patient-specific design for these therapies. Figure 1 Disclosures Kantarjian: BMS: Research Funding; Novartis: Research Funding; AbbVie: Honoraria, Research Funding; Jazz Pharma: Research Funding; Astex: Research Funding; Immunogen: Research Funding; Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Agios: Honoraria, Research Funding; Daiichi-Sankyo: Research Funding; Takeda: Honoraria; Amgen: Honoraria, Research Funding; Cyclacel: Research Funding; Ariad: Research Funding; Pfizer: Honoraria, Research Funding. Short:Takeda Oncology: Consultancy, Research Funding; AstraZeneca: Consultancy; Amgen: Honoraria. Cortes:Takeda: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding; Sun Pharma: Research Funding; BiolineRx: Consultancy; Novartis: Consultancy, Honoraria, Research Funding; Astellas Pharma: Consultancy, Honoraria, Research Funding; Merus: Consultancy, Honoraria, Research Funding; Immunogen: Consultancy, Honoraria, Research Funding; Biopath Holdings: Consultancy, Honoraria; Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Forma Therapeutics: Consultancy, Honoraria, Research Funding. Jabbour:Cyclacel LTD: Research Funding; Pfizer: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Adaptive: Consultancy, Research Funding. Molldrem:M. D. Anderson & Astellas Pharma: Other: Royalties.


1999 ◽  
Vol 189 (10) ◽  
pp. 1531-1544 ◽  
Author(s):  
Calvin B. Williams ◽  
Deborah L. Engle ◽  
Gilbert J. Kersh ◽  
J. Michael White ◽  
Paul M. Allen

We have developed a unique in vivo system to determine the relationship between endogenous altered peptide ligands and the development of major histocompatibility complex class II– restricted T cells. Our studies use the 3.L2 T cell receptor (TCR) transgenic mouse, in which T cells are specific for Hb(64–76)/I-Ek and positively selected on I-Ek plus self-peptides. To this endogenous peptide repertoire, we have individually added one of six well-characterized 3.L2 ligands. This transgenic approach expands rather than constrains the repertoire of self-peptides. We find that a broad range of ligands produce negative selection of thymocytes in vivo. When compared with the in vitro TCR–ligand binding kinetics, we find that these negatively selecting ligands all have a half-life of 2 s or greater. Additionally, one of two ligands examined with no detectable binding to the 3.L2 TCR and no activity on mature 3.L2 T cells (Q72) enhances the positive selection of transgenic thymocytes in vivo. Together, these data establish a kinetic threshold between negative and positive selection based on the longevity of TCR–ligand complexes.


2020 ◽  
Vol 295 (42) ◽  
pp. 14445-14457 ◽  
Author(s):  
Wael Awad ◽  
Erin W. Meermeier ◽  
Maria L. Sandoval-Romero ◽  
Jérôme Le Nours ◽  
Aneta H. Worley ◽  
...  

MR1 presents vitamin B–related metabolites to mucosal associated invariant T (MAIT) cells, which are characterized, in part, by the TRAV1-2+ αβ T cell receptor (TCR). In addition, a more diverse TRAV1-2− MR1-restricted T cell repertoire exists that can possess altered specificity for MR1 antigens. However, the molecular basis of how such TRAV1-2− TCRs interact with MR1–antigen complexes remains unclear. Here, we describe how a TRAV12-2+ TCR (termed D462-E4) recognizes an MR1–antigen complex. We report the crystal structures of the unliganded D462-E4 TCR and its complex with MR1 presenting the riboflavin-based antigen 5-OP-RU. Here, the TRBV29-1 β-chain of the D462-E4 TCR binds over the F′-pocket of MR1, whereby the complementarity-determining region (CDR) 3β loop surrounded and projected into the F′-pocket. Nevertheless, the CDR3β loop anchored proximal to the MR1 A′-pocket and mediated direct contact with the 5-OP-RU antigen. The D462-E4 TCR footprint on MR1 contrasted that of the TRAV1-2+ and TRAV36+ TCRs' docking topologies on MR1. Accordingly, diverse MR1-restricted T cell repertoire reveals differential docking modalities on MR1, thus providing greater scope for differing antigen specificities.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 831-831
Author(s):  
Robert Q. Le ◽  
J. Joseph Melenhorst ◽  
Brenna Hill ◽  
Sarfraz Memon ◽  
Minoo Battiwalla ◽  
...  

Abstract Abstract 831 After allogeneic stem cell transplantation (SCT), donor T lymphocyte immune function is slowly re-established in the recipient through reconstruction of the donor's post-thymic T cell repertoire and from T cell neogenesis in the thymus. Although long-term survivors from SCT appear healthy, their immune repertoire and differences from that of their donors have not been characterized. We studied 38 healthy patients surviving more than 10 years from a myeloablative SCT for hematological malignancy (median follow-up 12 years, range 10–16 years). T cell and natural killer (NK) cell repertoires in these patients were compared with cells from their stem cell donors cryopreserved at time of transplant and from the same donors at 10 year after SCT. The median age of both recipients and their sibling donors at time of transplant was identical (36 years). Patients received cyclosporine GVHD prophylaxis and delayed add-back of donor lymphocytes 30–90 days post transplant. Only one patient was on continued immunosuppressive treatment at the time of study. Compared with the donor pre-transplant counts there was no significant difference in the absolute lymphocyte, neutrophil, monocyte, CD4+ and CD8+ T cell, NK cell, and B cell subset counts. However, compared to their donors, recipients had a) significantly fewer naïve CD4+ and CD8+ T cells; b) lower T cell receptor excision circles levels; c) fewer CD4+ central memory T cells; d) more effector CD8+ T cells; e) and more FOXP3+ regulatory T cells. These data suggest that the patient had a persistent deficiency on T cell neogenesis. Molecular examination of the T cell receptor Vbeta (TCRBV) repertoire by spectratype analysis showed that there was no significant difference in total complexity score, defined as the sum of the number of discrete peaks for each Vbeta subfamily, between the patients and their donors. TCRBV subfamily spectratyping profiles of patients and donors, however, had diverged, with both gains and losses of peaks identifiable in both patient and donor. In conclusion, patients surviving 10 or more years after allogeneic SCT still show a T cell repertoire that reflects expansion of the donor-derived post thymic T cell compartment, with a limited contribution by new T cell generation and persistently increased Tregs. It therefore appears that a diverse TCRBV repertoire predominantly derived from the memory T cell pool is compatible with good health. Disclosures: No relevant conflicts of interest to declare.


1989 ◽  
Vol 19 (11) ◽  
pp. 2175-2177 ◽  
Author(s):  
Eric J. Jenkinson ◽  
Rosetta Kingston ◽  
Christopher A. Smith ◽  
Gwynn T. Williams ◽  
John J. T. Owen

1998 ◽  
Vol 188 (5) ◽  
pp. 897-907 ◽  
Author(s):  
Yoshinori Fukui ◽  
Osamu Hashimoto ◽  
Ayumi Inayoshi ◽  
Takahiro Gyotoku ◽  
Tetsuro Sano ◽  
...  

The T cell repertoire is shaped by positive and negative selection of thymocytes through the interaction of α/β-T cell receptors (TCR) with self-peptides bound to self-major histocompatibility complex (MHC) molecules. However, the involvement of specific TCR-peptide contacts in positive selection remains unclear. By fixing TCR-β chains with a single rearranged TCR-β irrelevant to the selecting ligand, we show here that T cells selected to mature on a single MHC–peptide complex express highly restricted TCR-α chains in terms of Vα usage and amino acid residue of their CDR3 loops, whereas such restriction was not observed with those selected by the same MHC with diverse sets of self-peptides including this peptide. Thus, we visualized the TCR structure required to survive positive selection directed by this single ligand. Our findings provide definitive evidence that specific recognition of self-peptides by TCR could be involved in positive selection of thymocytes.


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