Search results for "T cell"
showing 10 items of 2228 documents
Autoreactive liver-infiltrating T cells in primary biliary cirrhosis recognize inner mitochondrial epitopes and the pyruvate dehydrogenase complex.
1993
Primary biliary cirrhosis (PBC) is characterized by lymphoid infiltrates in the portal tracts of the liver and the occurrence of antimitochondrial autoantibodies in serum directed against components of the pyruvate dehydrogenase complex and the other alpha-keto acid dehydrogenase complexes. These enzymes are located on the inner mitochondrial membrane. The destruction of the biliary tract in PBC is thought to be mediated by autoreactive liver-infiltrating T cells exerting cytotoxic activity or releasing certain lymphokines. In this study the reactivity of liver infiltrating T cells was shown to a bovine pyruvate dehydrogenase complex (PDH), a purified E2 subunit (PDH-E2) and a crude prepara…
Reactivation of chronic type B hepatitis: the effect on expression of serum HBV-DNA and pre-S encoded proteins.
1988
Hepatitis B markers were studied in seven patients with reactivated liver disease. Reactivation of chronic type B hepatitis, as indicated by the reappearance of hepatitis B e antigen (HBeAg) in the serum, was characterised by the appearance of hepatitis B virus-DNA (HBV-DNA) in the serum. The expression of pre-S 1 encoded protein remained unchanged in five of seven patients, and poly-HSA as a marker for pre-S 2 encoded protein remained detectable in six of seven patients before and after reactivation of chronic hepatitis. The level of serum HBV-DNA correlated well with the level of liver enzymes, which rose from normal to various levels after reactivation of the liver disease. The data sugg…
Both IL-12p70 and IL-23 are synthesized during active Crohnʼs disease and are down-regulated by treatment with anti-IL-12 p40 monoclonal antibody
2005
Background: Interleukin (IL)-12p70 and IL-23 are key T helper-1 (TH1) cytokines that drive the inflammation seen in numerous models of intestinal inflammation. These molecules contain an identical p40 chain that is bound to a p35 chain in IL-12 and a p19 chain in IL-23, making both potentially susceptible to modulation by an anti-IL-12p40 monoclonal antibody (mAb). Methods: In the present study, we sought to determine whether active inflammation in Crohn's disease (CD) is associated with the increased synthesis of both of these cytokines and whether patients treated with an anti-IL-12p40 mAb down-regulate IL-23 as well as IL-12p70 as previous reported. Results: To this end we initially dete…
Pattern analysis of human cutaneous mast cell populations by total body surface mapping.
2003
SummaryBackground Mast cells (MCs), critical effector cells in allergic inflammation and innate immunity to bacteria, are located in large numbers in tissues that interface the external environment, including the skin. However, little is known about the distribution and numbers of human skin MCs. Objectives To assess the influence of age, sex and skin region on size and spatial distribution of MC populations in normal human skin. Methods Biopsies of healthy skin were obtained from 150 male and female individuals (age range 10–86 years). MCs were quantified and mapped planimetrically by histomorphometry in 15 anatomical sites (abdomen, thorax, lower and upper back, lower and upper arm, lower…
Functional patterns of cytomegalovirus (CMV) pp65 and immediate early-1-specific CD8+T cells that are associated with protection from and control of …
2015
Background The functional profile of cytomegalovirus (CMV)-specific CD8+ T cells that associate with protection from and control of CMV DNAemia in allogeneic stem cell transplant (allo-SCT) recipients remains incompletely characterized. Methods We enumerated pp65 and immediate early (IE)-1-specific CD8+ T cells expressing interferon-gamma, tumor necrosis factor-alpha, and CD107a, by flow cytometry in 94 patients at days +30 and +60 after allo-SCT. Results Fifty of 94 patients had CMV DNAemia within the first 100 days after transplant. CMV-specific CD8+ T-cell responses (of any functional type) were more likely to be detected in patients who did not display CMV DNAemia than in those who did …
Interferon-α Abrogates the Suppressive Effect of Apoptotic Cells on Dendritic Cells in anIn VitroModel of Systemic Lupus Erythematosus Pathogenesis
2013
Objective.An increased incidence of apoptotic cells and an increased activation of dendritic cells (DC) may be involved in the pathogenesis of systemic lupus erythematosus (SLE). We investigated the characteristics of apoptotic neutrophils and monocyte-derived DC of patients with SLE, their interaction, and the influence of autoantibodies and inflammatory cytokines on this interaction.Methods.Kinetics of neutrophil apoptosis and DC activation were studied by flow cytometry. To analyze the interaction of apoptotic cells with phagocytes, crossover coculture experiments were performed with DC from patients with SLE and apoptotic Jurkat T cells as well as with apoptotic neutrophils from patient…
Quantitative and functional analysis of core-specific T-helper cell and CTL activities in acute and chronic hepatitis B
2008
Aims/background CD4+ T-helper cell (Th) responses to hepatitis B virus (HBV) core antigen (HBc) are increased during exacerbations in acute and chronic hepatitis B (AHB, CHB) and might influence the induction of CD8+ cytotoxic T lymphocytes (CTL) that are important for viral clearance. Methods HBc-specific proliferative responses and cytokine release of blood mononuclear cells (PBMC) were studied in patients with AHB or CHB, as well as responders and non-responders to interferon-alpha treatment (IFN-R, IFN-NR), by [3H]-thymidine-uptake, enzyme-linked immunosorbent assay (ELISA) and Elispot assay and were compared to peptide HBc18 27-specific CTL precursor frequencies among CD8+ T cells deri…
Evidence for Less Marked Potential Signs of T-Cell Immunosenescence in Centenarian Offspring Than in the General Age-Matched Population
2014
People may reach the upper limits of the human life span at least partly because they have maintained more appropriate immune function, avoiding changes to immunity termed "immunosenescence." Exceptionally long-lived people may be enriched for genes that contribute to their longevity, some of which may bear on immune function. Centenarian offspring would be expected to inherit some of these, which might be reflected in their resistance to immunosenescence, and contribute to their potential longevity. We have tested this hypothesis by comparing centenarian offspring with age-matched controls. We report differences in the numbers and proportions of both CD4(+) and CD8(+) early- and late-diffe…
Sex-specific phenotypical and functional differences in peripheral human Vγ9/Vδ2 T cells
2006
Abstract Vγ9/Vδ2 T cells constitute a minor proportion of human peripheral blood T cells that can expand rapidly upon infection with microbial pathogens. Vγ9/Vδ2 T cell numbers change characteristically with age, rising from birth to puberty and gradually decreasing again beyond 30 years of age. In adults, female blood donors have significantly higher levels than males, implying that circulating Vγ9/Vδ2 T cells in women remain elevated for a longer period in life and drop less strikingly than in men. This loss in men is accompanied by a substantial depletion of CD27−CD45RA− and CD27−CD45RA+ effector T cells and a parallel increase in CD27+CD45RA− central memory T cells while in women, the d…
gamma-Interferon, interleukin-4 and interleukin-6 in vitro production in old subjects.
1993
It is well known that ageing is associated with various alterations of the lymphoid cell functions. Although both B and T cell are affected, the last appear to be more sensitive to ageing process. During the past years, to gain insight into thé mechanism(s) of this impairment, effort has been centered on the helper T cells specifically engaged in the production of interleukin-2 (IL-2) because of the pivotal role played by this cytokine in the activation of several immune functions. The results have demonstrated that the ability to produce IL-2 declines with age. In this paper we report the results of a study performed to determine the influence of age on the capacity to produce gamma-interf…