scholarly journals Identification of CD112R as a novel checkpoint for human T cells

2016 ◽  
Vol 213 (2) ◽  
pp. 167-176 ◽  
Author(s):  
Yuwen Zhu ◽  
Alessandro Paniccia ◽  
Alexander C. Schulick ◽  
Wei Chen ◽  
Michelle R. Koenig ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
T Cell Response ◽  
High Affinity ◽  
Poliovirus Receptor ◽  
Human T Cell ◽  
Human T Cells ◽  
Antigen Presenting

T cell immunoglobulin and ITIM domain (TIGIT) and CD226 emerge as a novel T cell cosignaling pathway in which CD226 and TIGIT serve as costimulatory and coinhibitory receptors, respectively, for the ligands CD155 and CD112. In this study, we describe CD112R, a member of poliovirus receptor–like proteins, as a new coinhibitory receptor for human T cells. CD112R is preferentially expressed on T cells and inhibits T cell receptor–mediated signals. We further identify that CD112, widely expressed on antigen-presenting cells and tumor cells, is the ligand for CD112R with high affinity. CD112R competes with CD226 to bind to CD112. Disrupting the CD112R–CD112 interaction enhances human T cell response. Our experiments identify CD112R as a novel checkpoint for human T cells via interaction with CD112.

scholarly journals Inhibition or activation of human T cell receptor transfectants is controlled by defined, soluble antigen arrays.

1992 ◽  
Vol 176 (5) ◽  
pp. 1421-1430 ◽  
Author(s):  
D E Symer ◽  
R Z Dintzis ◽  
D J Diamond ◽  
H M Dintzis
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Interleukin 2 ◽  
Cell Receptor ◽  
Jurkat Cells ◽  
Soluble Antigen ◽  
Human T Cell ◽  
Human T Cells ◽  
Binding Avidity

We present evidence that direct T cell receptor (TCR) occupancy by antigen can either activate or inhibit T cells, depending upon whether or not a threshold number of local TCRs are crosslinked by multivalent arrays of the antigen. Variants of Jurkat cells were previously transfected with TCR alpha and beta chains that bind fluorescein, yielding FL-TCR+ human T cells. The transfectants are activated upon binding soluble multivalent antigen arrays at concentrations well below those required for monovalent interactions. This activation, measured by calcium fluxes and interleukin 2 (IL-2) production, indicates the superior binding avidity of multivalent ligands. Smaller, less multivalent arrays do not activate the cells, but antagonize larger arrays, demonstrating that antigen can bind TCR as either agonist or antagonist. The balance between activation and inhibition depends upon antigen array size, ligand valence, and concentration, indicating that a threshold extent of receptor crosslinking, and not individual perturbations of single TCR, is required for activation by antigen. Approximately 100 stimulatory arrays specifically bind per FL-TCR+ cell at concentrations where IL-2 production is half-maximal.

scholarly journals Cd8− T Cell Transfectants That Express a High Affinity T Cell Receptor Exhibit Enhanced Peptide-Dependent Activation

2001 ◽  
Vol 194 (8) ◽  
pp. 1043-1052 ◽  
Author(s):  
Phillip D. Holler ◽  
Alice R. Lim ◽  
Bryan K. Cho ◽  
Laurie A. Rund ◽  
David M. Kranz
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cytotoxic T Lymphocyte ◽  
Cell Activity ◽  
Cell Receptor ◽  
Wild Type ◽  
High Affinity ◽  
Antigen Presenting

T cells are activated by binding of the T cell receptor (TCR) to a peptide-major histocompatibility complex (MHC) complex (pMHC) expressed on the surface of antigen presenting cells. Various models have predicted that activation is limited to a narrow window of affinities (or dissociation rates) for the TCR–pMHC interaction and that above or below this window, T cells will fail to undergo activation. However, to date there have not been TCRs with sufficiently high affinities in order to test this hypothesis. In this report we examined the activity of a CD8-negative T cell line transfected with a high affinity mutant TCR (KD = 10 nM) derived from cytotoxic T lymphocyte clone 2C by in vitro engineering. The results show that despite a 300-fold higher affinity and a 45-fold longer off-rate compared with the wild-type TCR, T cells that expressed the mutant TCRs were activated by peptide. In fact, activation could be detected at significantly lower peptide concentrations than with T cells that expressed the wild-type TCR. Furthermore, binding and functional analyses of a panel of peptide variants suggested that pMHC stability could account for apparent discrepancies between TCR affinity and T cell activity observed in several prior studies.

scholarly journals Induction of lysosomal and plasma membrane-bound sialidases in human T-cells via T-cell receptor

2004 ◽  
Vol 380 (2) ◽  
pp. 425-433 ◽  
Author(s):  
Peng WANG ◽  
Ji ZHANG ◽  
Hong BIAN ◽  
Ping WU ◽  
Reshma KUVELKAR ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cell Receptor ◽  
Th2 Cytokines ◽  
Receptor Stimulation ◽  
Human T Cell ◽  
Human T Cells

Among the three isoenzymes of neuraminidase (Neu) or sialidase, Neu-1 has been suggested to be induced by cell activation and to be involved in IL (interleukin)-4 biosynthesis in murine T-cells. In the present study, we found that antigen-induced airway eosinophilia, a typical response dependent on Th2 (T-helper cell type 2) cytokines, as well as mRNA expression of Th2 cytokines, including IL-4, are suppressed in Neu-1-deficient mice, thereby demonstrating the in vivo role of murine Neu-1 in regulation of Th2 cytokines. To elucidate the roles of various sialidases in human T-cell activation, we investigated their tissue distribution, gene induction and function. Neu-1 is the predominant isoenzyme at the mRNA level in most tissues and cells in both mice and humans, including T-cells. T-cells also have significant levels of Neu-3 mRNAs, albeit much lower than those of Neu-1, whereas the levels of Neu-2 mRNAs are minimal. In human T-cells, both Neu-1 and Neu-3 mRNAs are significantly induced by T-cell-receptor stimulation, as is sialidase activity against 4-methylumbelliferyl-N-acetylneuramic acid (a substrate for both Neu-1 and Neu-3) and the ganglioside GD1a [NeuAcα2-3Galβ1-3GalNAcβ1-4(NeuAcα2-3)Galβ1-4Glcβ1-cer] (a substrate for Neu-3, but not for Neu-1). The expression of the two sialidase genes may be under differential regulation. Western blot analysis and enzymic comparison with recombinant sialidases have revealed that Neu-3 is induced as a major isoform in activated cells. The induction of Neu-1 and Neu-3 in T-cells is unique. In human monocytes and neutrophils stimulated with various agents, the only observation of sialidase induction has been by IL-1 in neutrophils. Functionally, a major difference has been observed in Jurkat T-cell lines over-expressing Neu-1- and Neu-3. Upon T-cell receptor stimulation, IL-2, interferon-γ, IL-4 and IL-13 are induced in the Neu-1 line, whereas in the Neu-3 line the same cytokines are induced, with the exception of IL-4. Taken together, these results suggest an important immunoregulatory role for both Neu-1 and Neu-3 in humans.

scholarly journals Characterization of human T cells reactive with the Mycoplasma arthritidis-derived superantigen (MAM): generation of a monoclonal antibody against V beta 17, the T cell receptor gene product expressed by a large fraction of MAM-reactive human T cells.

1991 ◽  
Vol 174 (4) ◽  
pp. 891-900 ◽  
Author(s):  
S M Friedman ◽  
M K Crow ◽  
J R Tumang ◽  
M Tumang ◽  
Y Q Xu ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Activity ◽  
Cell Receptor ◽  
Cytotoxic T Cell ◽  
Mycoplasma Arthritidis ◽  
Human T Cells

While all known microbial superantigens are mitogenic for human peripheral blood lymphocytes (PBL), the functional response induced by Mycoplasma arthritidis-derived superantigen (MAM) is unique in that MAM stimulation of PBL consistently results in T cell-dependent B cell activation characterized by polyclonal IgM and IgG production. These immunostimulatory effects of MAM on the humoral arm of the human immune system warranted a more precise characterization of MAM-reactive human T cells. Using an uncloned MAM reactive human T cell line as immunogen, we have generated a monoclonal antibody (mAb) (termed C1) specific for the T cell receptor V beta gene expressed by the major fraction of MAM-reactive human T cells, V beta 17. In addition, a V beta 17- MAM-reactive T cell population exists, assessed by MAM, induced T cell proliferation and cytotoxic T cell activity. mAb C1 will be useful in characterizing the functional properties of V beta 17+ T cells and their potential role in autoimmune disease.

scholarly journals In Vivo Selection of T-Cell Receptor Junctional Region Sequences by HLA-A2 Human T-Cell Lymphotropic Virus Type 1 Tax11-19 Peptide Complexes

2001 ◽  
Vol 75 (2) ◽  
pp. 1065-1071 ◽  
Author(s):  
Mineki Saito ◽  
Graham P. Taylor ◽  
Akiko Saito ◽  
Yoshitaka Furukawa ◽  
Koichiro Usuku ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Virus Type ◽  
Cell Receptor ◽  
Antigen Specificity ◽  
Human T Cell ◽  
Cdr3 Region

ABSTRACT Using HLA-peptide tetrameric complexes, we isolated human T-cell lymphotrophic virus type 1 Tax peptide-specific CD8+ T cells ex vivo. Antigen-specific amino acid motifs were identified in the T-cell receptor Vβ CDR3 region of clonally expanded CD8+ T cells. This result directly confirms the importance of the CDR3 region in determining the antigen specificity in vivo.

Expression of T-cell receptor α and β variable genes in normal and malignant human T cells

1993 ◽  
Vol 84 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Huaizhong Hu ◽  
Màrio Rui Queirò ◽  
Marcel G. J. Tilanus ◽  
Roel A. Weger ◽  
Henk-Jan Schuurman
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
Human T Cells ◽  
Variable Genes

scholarly journals The ht beta gene encodes a novel CACCC box-binding protein that regulates T-cell receptor gene expression

1993 ◽  
Vol 13 (9) ◽  
pp. 5691-5701
Author(s):  
Y Wang ◽  
J A Kobori ◽  
L Hood
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Binding Protein ◽  
Cell Receptor ◽  
Regulatory Function ◽  
Human T Cell ◽  
Alpha Gene ◽  
Beta Gene

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.

CD4+ T cells specific for glycoprotein B from cytomegalovirus exhibit extreme conservation of T-cell receptor usage between different individuals

Blood ◽  
2008 ◽  
Vol 111 (4) ◽  
pp. 2053-2061 ◽  
Author(s):  
Laura Crompton ◽  
Naeem Khan ◽  
Rajiv Khanna ◽  
Laxman Nayak ◽  
Paul A. H. Moss
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Response ◽  
Cd4 T Cells ◽  
Clonal Selection ◽  
Cell Receptor ◽  
T Cell Response ◽  
Cd4 T Cell ◽  
Extreme Conservation

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.

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