scholarly journals In a small multideterminant peptide, each determinant is recognized by a different V beta gene segment.

1992 ◽  
Vol 176 (1) ◽  
pp. 297-302 ◽  
Author(s):  
N K Nanda ◽  
K K Arzoo ◽  
E E Sercarz

Given the vast potential for diversification of the T cell receptor (TCR) repertoire and the fact that V(a) beta mice exist in the wild, it would have been predicted that in spite of the absence of 10 TCR V beta gene segments, V(a) beta mice would still have been able to produce an antigen-specific T cell response to all determinants. We have recently shown that Vb beta mice, with a wild-type TCR V beta repertoire, respond to peptide 110-121 of sperm whale myoglobin, with a majority of T cells expressing TCR V beta 8.2 and restricted to a hybrid I-A(d)/I-E(d) major histocompatibility complex molecule, and a smaller number of T cells expressing TCR V beta 8.1 and restricted to the I-A(d) molecule. However, V(a) beta mice, lacking members of the TCR V beta 8 gene family, responded only with I-A(d)-restricted T cells. Thus, it appeared that the I-A(d)-restricted response was less constrained, or more plastic. We now show that the two separate panels of I-A(d)-restricted T cell hybrids derived from V(a) beta or Vb beta mice in fact recognize distinct determinants within the same peptide 110-121. The determinant recognized by V(a) beta T cells is NH2 terminal (core: 110-118) with an absolute requirement for the residue Ala-110 for a successful interaction with TCRs. On the other hand, Vb beta T cells recognize the COOH-terminal region (core: 112-118) on the same peptide with an absolute requirement for COOH-terminal residue 118. In the dominance hierarchy displayed by the three distinct determinants of peptide 110-121, V(a) beta mice cannot recognize the two most dominant: the hybrid I-A(d)/I-E(d)-restricted determinant and the COOH-terminal, I-A(d)-restricted determinant. They instead respond with T cells specific for a third, distinctly NH2-terminal determinant. Our results show a strict association between recognition of a particular specificity and TCR V beta usage. This evidence suggests that even when a small peptide induces a heterogenous group of TCR V beta S, this need not be considered evidence for plasticity. Rather, at the level of individual determinants within the peptide, the results can point in the opposite direction, towards serious constraints in recognition at the level of V beta expression.

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 2344 ◽  
Author(s):  
Preeti Sharma ◽  
David M. Kranz

Adoptive T-cell therapies have shown exceptional promise in the treatment of cancer, especially B-cell malignancies. Two distinct strategies have been used to redirect the activity of ex vivo engineered T cells. In one case, the well-known ability of the T-cell receptor (TCR) to recognize a specific peptide bound to a major histocompatibility complex molecule has been exploited by introducing a TCR against a cancer-associated peptide/human leukocyte antigen complex. In the other strategy, synthetic constructs called chimeric antigen receptors (CARs) that contain antibody variable domains (single-chain fragments variable) and signaling domains have been introduced into T cells. Whereas many reviews have described these two approaches, this review focuses on a few recent advances of significant interest. The early success of CARs has been followed by questions about optimal configurations of these synthetic constructs, especially for efficacy against solid tumors. Among the many features that are important, the dimensions and stoichiometries of CAR/antigen complexes at the synapse have recently begun to be appreciated. In TCR-mediated approaches, recent evidence that mutated peptides (neoantigens) serve as targets for endogenous T-cell responses suggests that these neoantigens may also provide new opportunities for adoptive T-cell therapies with TCRs.


1991 ◽  
Vol 174 (1) ◽  
pp. 83-92 ◽  
Author(s):  
G Ruberti ◽  
A Gaur ◽  
C G Fathman ◽  
A M Livingstone

T cell clones recognizing the sperm whale myoglobin (SpWMb) epitope 110-121 in association with H-2d major histocompatibility complex class II molecules display a very limited heterogeneity of T cell receptor (TCR) V beta usage in DBA/2 mice. All clones previously tested used the same V beta 8.2 gene segment and very restricted junctional regions. To investigate the significance of this observation in vivo, we immunized DBA/2 mice with the intact SpW Mb protein or peptide 110-121. Only the V beta 8+ T cells showed any significant response to the 110-121 epitope. The response to peptide 110-121 was then analyzed in mice which, either as a consequence of antibody depletion or through genetic deletion of TCR V beta genes, lacked V beta 8+ peripheral T cells. DBA/2 mice depleted of V beta 8+ T cells by antibody treatment responded poorly to the 110-121 peptide, and only at high antigen concentrations. In contrast, DBA/2V beta a mice (homozygous for a deletion of multiple V beta gene segments including the V beta 8 family) made a response at least as great as that made by DBA/2 mice, even though the DBA/2V beta a mice had a very restricted TCR V beta repertoire compared with DBA/2 mice. Mechanisms which might determine differences in the 110-121 specific response of DBA/2, DBA/2V beta a and F23.1-treated DBA/2 mice are discussed.


Genome ◽  
1989 ◽  
Vol 31 (2) ◽  
pp. 652-655 ◽  
Author(s):  
Michael Steinmetz ◽  
Horst Blüthmann ◽  
Stefan Ryser ◽  
Yasushi Uematsu

Transgenic mice have been obtained with genes coding for an αβ T-cell receptor that recognizes the male-specific antigen H-Y in association with the Db class I major histocompatibility complex molecule. Most if not all of the T-cells express the β chain encoded by the transgene and show allelic exclusion of endogenous β genes. In contrast, the expression of the α transgene does not completely block rearrangement and formation of functional endogenous α genes. In H-2b transgenic female mice the transgenic T-cell receptor is functionally expressed on at least 30% of CD8+ peripheral T-lymphocytes as indicated by their ability to lyse male target cells. Also in transgenic H-2b male mice a large proportion of peripheral T-cells appear to express the transgenic receptor. However, these cells do not react with male target cells because they show only low level or no expression of CD8 cell interaction molecules. Tolerance is established in the male transgenic thymus through deletion of CD4+CD8+ immature thymocytes.Key words: transgenic mice, immune system, T-lymphocytes, T-cell receptor, tolerance, CD8 surface antigen, enhancer, gene rearrangement, allelic exclusion.


1988 ◽  
Vol 168 (5) ◽  
pp. 1899-1916 ◽  
Author(s):  
J A Bluestone ◽  
R Q Cron ◽  
M Cotterman ◽  
B A Houlden ◽  
L A Matis

Analyses of TCR-bearing murine and human T cells have defined a unique subpopulation of T cells that express the TCR-gamma/delta proteins. The specificity of TCR-gamma/delta T cells and their role in the immune response have not yet been elucidated. Here we examine alloreactive TCR-gamma/delta T cell lines and clones that recognize MHC-encoded antigens. A BALB/c nu/nu (H-2d)-derived H-2k specific T cell line and derived clones were both cytolytic and released lymphokines after recognition of a non-classical H-2 antigen encoded in the TL region of the MHC. These cells expressed the V gamma 2/C gamma 1 protein in association with a TCR-delta gene product encoded by a Va gene segment rearranged to two D delta and one J delta variable elements. A second MHC-specific B10 nu/nu (H-2b) TCR-gamma/delta T cell line appeared to recognize a classical H-2D-encoded MHC molecule and expressed a distinct V gamma/C gamma 4-encoded protein. These data suggest that many TCR-gamma/delta-expressing T cells may recognize MHC-linked antigens encoded within distinct subregions of the MHC. The role of MHC-specific TCR-gamma/delta cells in immune responses and their immunological significance are discussed.


1993 ◽  
Vol 13 (9) ◽  
pp. 5691-5701
Author(s):  
Y Wang ◽  
J A Kobori ◽  
L Hood

A gene encoding a novel CACCC box-binding protein that binds to the promoter region of the human T-cell receptor (TCR) V beta 8.1 gene and the mouse TCR alpha gene silencer has been cloned. This gene, termed ht beta, contains four zinc fingers of the class Cys2-X12-His2 that may be responsible for DNA binding and a highly negatively charged region that defines a putative transcriptional activation domain. Analysis of the expression of ht beta mRNA revealed similar expression levels and patterns in various cell lines. The bacterially expressed ht beta protein can bind to the CACCC box in both the human TCR V beta 8.1 gene promoter and the mouse TCR alpha gene silencer. The CACCC box is essential for efficient transcription of the V beta 8.1 promoter. Cotransfection with an ht beta expression plasmid and a reporter vector indicated that ht beta can activate human TCR V beta 8.1 gene transcription. ht beta also is able to counteract the silencing effect of the mouse TCR alpha gene silencer. The CACCC box has been found in almost all V beta 8.1 gene subfamily members and in both TCR alpha and beta gene enhancers in humans and mice. These results suggest that the CACCC box-binding protein may have an important regulatory function for TCR gene expression in alpha beta T cells versus gamma delta T cells.


1993 ◽  
Vol 177 (2) ◽  
pp. 387-395 ◽  
Author(s):  
G E Osman ◽  
M Toda ◽  
O Kanagawa ◽  
L E Hood

Collagen type II-induced arthritis (CIA) is generated in susceptible rodent strains by intradermal injections of homologous or heterologous native type II collagen in complete Freund's adjuvant. Symptoms of CIA are analogous to those of the human autoimmune disease, rheumatoid arthritis. CIA is a model system for T cell-mediated autoimmune disease. To study the T cell receptor (TCR) repertoire of bovine type II-specific T cells that may be involved in the pathogenesis of CIA in DBA/1Lac.J (H-2q) mice, 13 clonally distinct T cell hybridomas specific for bovine type II collagen have been established and the alpha and beta chains of their TCRs have been analyzed. These T cell hybridomas recognize epitopes that are shared by type II collagens from distinct species and not by type I collagens, and exhibit a highly restricted TCR-alpha/beta repertoire. The alpha chains of the TCRs employ three V alpha gene subfamilies (V alpha 11, V alpha 8, and V alpha 22) and four J alpha gene segments (J alpha 42, J alpha 24, J alpha 37, and J alpha 32). The V alpha 22 is a newly identified subfamily consisting of approximately four to six members, and exhibits a high degree of polymorphism among four mouse strains of distinct V alpha haplotypes. In addition, the beta chains of the TCRs employ three V beta gene subfamilies (V beta 8, V beta 1, and V beta 6), however the V beta 8.2 gene segment is preferentially utilized (58.3%). In contrast, the J beta gene segment usage is more heterogeneous. On the basis of the highly limited TCR-alpha/beta repertoire of the TCRs of the panel of bovine type II-specific T cell hybrid clones, a significant reduction (60%) of the incidence of arthritis in DBA/1Lac.J mice is accomplished by the use of anti-V beta 8.2 antibody therapy.


Blood ◽  
2008 ◽  
Vol 111 (4) ◽  
pp. 2053-2061 ◽  
Author(s):  
Laura Crompton ◽  
Naeem Khan ◽  
Rajiv Khanna ◽  
Laxman Nayak ◽  
Paul A. H. Moss

Antigen-specific CD8+ cytotoxic T cells often demonstrate extreme conservation of T-cell receptor (TCR) usage between different individuals, but similar characteristics have not been documented for CD4+ T cells. CD4+ T cells predominantly have a helper immune role, but a cytotoxic CD4+ T-cell subset has been characterized, and we have studied the cytotoxic CD4+ T-cell response to a peptide from human cytomegalovirus glycoprotein B presented through HLA-DRB*0701. We show that this peptide elicits a cytotoxic CD4+ T-cell response that averages 3.6% of the total CD4+ T-cell repertoire of cytomegalovirus-seropositive donors. Moreover, CD4+ cytotoxic T-cell clones isolated from different individuals exhibit extensive conservation of TCR usage, which indicates strong T-cell clonal selection for peptide recognition. Remarkably, this TCR sequence was recently reported in more than 50% of cases of CD4+ T-cell large granular lymphocytosis. Immunodominance of cytotoxic CD4+ T cells thus parallels that of CD8+ subsets and suggests that cytotoxic effector function is critical to the development of T-cell clonal selection, possibly from immune competition secondary to lysis of antigen-presenting cells. In addition, these TCR sequences are highly homologous to those observed in HLA-DR7+ patients with CD4+ T-cell large granular lymphocytosis and implicate cytomegalovirus as a likely antigenic stimulus for this disorder.


1994 ◽  
Vol 180 (3) ◽  
pp. 1171-1176 ◽  
Author(s):  
P Dellabona ◽  
E Padovan ◽  
G Casorati ◽  
M Brockhaus ◽  
A Lanzavecchia

The T cell receptor (TCR)-alpha/beta CD4-8- (double negative, DN) T cell subset is characterized by an oligoclonal repertoire and a restricted V gene usage. By immunizing mice with a DN T cell clone we generated two monoclonal antibodies (mAbs) against V alpha 24 and V beta 11, which have been reported to be preferentially expressed in DN T cells. Using these antibodies, we could investigate the expression and pairing of these V alpha and V beta gene products among different T cell subsets. V alpha 24 is rarely expressed among CD4+ and especially CD8+ T cells. In these cases it is rearranged to different J alpha segments, carries N nucleotides, and pairs with different V beta. Remarkably, V alpha 24 is frequently expressed among DN T cells and is always present as an invariant rearrangement with J alpha Q, without N region diversity. This invariant V alpha 24 chain is always paired to V beta 11. This unique V alpha 24-J alpha Q/V beta 11 TCR was found in expanded DN clones from all the individuals tested. These findings suggest that the frequent occurrence of cells carrying this invariant TCR is due to peripheral expansion of rare clones after recognition of a nonpolymorphic ligand.


Blood ◽  
2009 ◽  
Vol 114 (11) ◽  
pp. 2244-2253 ◽  
Author(s):  
Michael Rist ◽  
Corey Smith ◽  
Melissa J. Bell ◽  
Scott R. Burrows ◽  
Rajiv Khanna

Abstract The ability of CD8+ T cells to engage a diverse range of peptide–major histocompatibility complex (MHC) complexes can also lead to cross-recognition of self and nonself peptide-MHC complexes and thus directly contribute toward allograft rejection or autoimmunity. Here we present a novel form of cross-recognition by herpes virus–specific CD8+ cytotoxic T cells that challenges the current paradigm of self/non-self recognition. Functional characterization of a human leukocyte antigen (HLA) Cw*0602-restricted cytomegalovirus-specific CD8+ T-cell response revealed an unusual dual specificity toward a pp65 epitope and the alloantigen HLA DR4. This cross-recognition of HLA DR4 alloantigen was critically dependent on the coexpression of HLA DM and was preferentially directed toward the B-cell lineage. Furthermore, allostimulation of peripheral blood lymphocytes with HLA DRB*0401-expressing cells rapidly expanded CD8+ T cells, which recognized the pp65 epitope in the context of HLA Cw*0602. T-cell repertoire analysis revealed 2 dominant populations expressing T-cell receptor beta variable (TRBV)4-3 or TRBV13, with cross-reactivity exclusively mediated by the TRBV13+ clonotypes. More importantly, cross-reactive TRBV13+ clonotypes displayed markedly lower T-cell receptor binding affinity and a distinct pattern of peptide recognition, presumably mimicking a structure presented on the HLA DR4 allotype. These results illustrate a novel mechanism whereby virus-specific CD8+ T cells can cross-recognize HLA class II molecules and may contribute toward allograft rejection and/or autoimmunity.


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