Search results for "a-bet"
showing 8 items of 68 documents
Human leucocyte antigen-A2 restricted and Mycobacterium tuberculosis 19-kDa antigen-specific CD8+ T-cell responses are oligoclonal and exhibit a T-ce…
2001
CD8+ T cells can be grouped into two different types of secretory T lymphocytes, based on the cytokine-secretion pattern upon antigen exposure: those with a T-cell cytotoxic type 1 response (Tc1), which secrete interferon-gamma (IFN-gamma), or those with a T-cell cytotoxic type 2 response, which secrete interleukin (IL)-4 and IL-10. We examined the CD8+ T-cell response directed against an immunodominant human leucocyte antigen (HLA)-A2-presented peptide derived from a 19-kDa Mycobacterium tuberculosis-associated antigen. T cells were examined by functional analysis and by T-cell receptor (TCR) complementarity-determining region 3 (CDR3)-spectratyping, which defines the complexity of a T-cel…
T Cell Receptor Mimic Peptidesand Their Potential Application in T-Cell-Mediated Diseas e
2001
<i>Background:</i> A T cell receptor (TCR) peptide was designed that mimics the intramembranous amino acid sequence of the TCR chain. Prior studies had shown that this mimic peptide would inhibit TCR signaling. This study was designed to investigate the use of this mimic peptide for the treatment of T-cell-mediated skin diseases. <i>Methods:</i> Synthesized mimic peptides were first tested for their T-cell-inhibitory effect in proliferation assays. Afterwards, mimic peptides were applied to murine ear skin prior to application of a contact allergen and tested for their inhibitory effect in the model of murine allergic contact sensitivity. The effect of epicutaneous t…
IL-23 receptor regulates unconventional IL-17-producing T cells that control bacterial infections.
2010
AbstractIL-23 plays an important role in autoimmune tissue inflammation and induces the generation of not fully characterized effector cells that mediate protection against pathogens. In this paper, we established the essential role of IL-23R in the host response against intracellular pathogens. IL-23 was critical for the expansion or maintenance of γδ and double negative (DN) αβ T cells. These cells were rapidly recruited to the site of infection and produced large amounts of IL-17, IFN-γ, and TNF-α. Notably, DN T cells transferred into L. monocytogenes-infected RAG2−/− mice prevented bacterial growth, confirming their protective role against intracellular pathogens. Our results show that …
TCR V alpha chain expression influences reactivity to the hapten TNP.
1997
We have recently demonstrated a remarkable selection of in vitro cultivated, TNP-specific polyclonal T cell lines for the expression of a TCR beta chain encoded by the V beta 8.2 gene. The goal of the present study was to analyse V alpha usage in V beta 8.2 T cells responsive to TNP, using TNP-specific T cell lines derived from three common strains of mice, as well as from V beta 8.2 transgenic mice. Results indicate that in vitro TNP stimulation of T cells from TNP-immune mice results in significant skewing of V alpha usage among responding V beta 8.2+ T cells, with overexpression observed for V alpha 3.2 and V alpha 8. These results indicate that V alpha expression influences recognition …
Human γδ T-Cells: From Surface Receptors to the Therapy of High-Risk Leukemias
2018
γδ T lymphocytes are potent effector cells, capable of efficiently killing tumor and leukemia cells. Their activation is mediated by γδ T-cell receptor (TCR) and by activating receptors shared with NK cells (e.g., NKG2D and DNAM-1). γδ T-cell triggering occurs upon interaction with specific ligands, including phosphoantigens (for Vγ9Vδ2 TCR), MICA-B and UL16 binding protein (for NKG2D), and PVR and Nectin-2 (for DNAM-1). They also respond to cytokines undergoing proliferation and release of cytokines/chemokines. Although at the genomic level γδ T-cells have the potential of an extraordinary TCR diversification, in tissues they display a restricted repertoire. Recent studies have identified …
Transferrin gene expression in the mammary gland of the rat. The enhancing effect of 17 beta-oestradiol on the level of RNA is tissue-specific.
1993
We have investigated the physiological factors which regulate transferrin gene expression in the mammary gland of the rat. Our studies by dot blot analysis have demonstrated that multiple doses of 17β-oestradiol (OE2; 0·5 mg/kg per day for 3 days) elicit a specific 3·5-fold increase in the transferrin mRNA levels in the mammary glands of virgin rats. The hormonal action of OE2 in mammary tissue was specific for the transferrin gene, as judged by hybridization with β-actin cDNA. The accmulation of transferrin mRNA induced by OE2 treatment was similar to the developmentally regulated expression of the gene observed during the reproductive cycle. The steady-state level of mammary transferrin m…
HLA-B27-restricted T cells from patients with ankylosing spondylitis recognize peptides from B*2705 that are similar to bacteria-derived peptides
2003
SUMMARY Ankylosing spondylitis (AS) is an inflammatory systemic disease affecting the spine, sacroiliacal and peripheral joints. Although the aetiology of AS remains unknown, the strong association with the HLA-B27 allele might reflect directly a detrimental effect of the HLA-B27 molecule itself, resulting from its potential capability to present ‘arthritogenic’ peptides to CD8+ T cells. Because some forms of SpA are triggered by enterobacterial infection, such arthritogenic peptides might originate from autologous and/or bacterial proteins triggering cross-reactive CD8+ T cell clones. Intriguingly, two peptides from the second extracellular domain of HLA-B*2705 share sequence homologies wi…
HLA-B27-restricted cytotoxic T lymphocyte responses to arthritogenic enterobacteria or self-antigens are dominated by closely related TCRBV gene segm…
1996
Identification of the T-cell receptors (TCR) used by synovial cytotoxic T lymphocytes (CTL) of patients with reactive arthritis (ReA) may be crucial to better understanding the pathogenetic mechanism underlying the HLA-B27 association of spondylarthropathies. The authors, therefore, sequenced 25 TCRB chains from HLA-B27-restricted CD8+ CTL clones and two clonal lines specific for self- or Yersinia enterocolitica antigen isolated from synovial fluids of 3 HLA-B27+ patients with ReA and PBL of one healthy HLA-B27+ individual. Fourteen non-HLA-B27-restricted CTL served as controls. Both autoreactive and Y. enterocolitica specific HLA-B27-restricted CTL used a highly limited set of VB genes wit…