Search results for "T CELLS"
showing 10 items of 498 documents
Genome-based in silico identification of new Mycobacterium tuberculosis antigens activating polyfunctional CD8+ T cells in human tuberculosis.
2011
Although CD8(+) T cells help control Mycobacterium tuberculosis infection, their M. tuberculosis Ag repertoire, in vivo frequency, and functionality in human tuberculosis (TB) remains largely undefined. We have performed genome-based bioinformatics searches to identify new M. tuberculosis epitopes presented by major HLA class I supertypes A2, A3, and B7 (covering 80% of the human population). A total of 432 M. tuberculosis peptides predicted to bind to HLA-A*0201, HLA-A*0301, and HLA-B*0702 (representing the above supertypes) were synthesized and HLA-binding affinities determined. Peptide-specific CD8(+) T cell proliferation assays (CFSE dilution) in 41 M. tuberculosis-responsive donors ide…
Activation of cutaneous immune responses in complex regional pain syndrome
2014
The pathogenesis of complex regional pain syndrome (CRPS) is unresolved, but tumor ne- crosis factor alpha (TNF-a) and interleukin-6 (IL-6) are elevated in experimental skin blister fluid from CRPS-affected limbs, as is tryptase, a marker for mast cells. In the rat fracture model of CRPS, exag- gerated sensory and sympathetic neural signaling stimulate keratinocyte and mast cell proliferation, causing the local production of high levels of inflammatory cytokines leading to pain behavior. The current investigation used CRPS patient skin biopsies to determine whether keratinocyte and mast cell proliferation occur in CRPS skin and to identify the cellular source of the up-regulated TNF-a, IL-6…
B and T cell immune responses elicited by the Comirnaty® COVID-19 vaccine in nursing home residents
2021
Objectives The immunogenicity of the Comirnaty® COVID-19 vaccine is understudied in elderly people with comorbidities. SARS-CoV-2-S-targeted antibody and T cell responses following full vaccination were assessed in nursing home residents. Methods Sixty nursing home residents (44 female; age, 53-100 years), of whom 10 had previously been diagnosed of COVID-19, and 18 healthy controls (15 female; age, 27-54 years) were recruited. Pre- and post-vaccination blood specimens were available for quantitation of total antibodies binding SARS-CoV-2 S protein and enumeration of SARS-CoV-2-S-reactive IFN-γ CD4+ and CD8+ T cells by flow cytometry. Results The seroconversion rate in presumably SARS-CoV-2…
Characterization of γδ T cells in intestinal mucosa from patients with early onset or long standing inflammatory bowel disease and their correlation …
2019
Abstract Background and Aims Inflammatory bowel disease [IBD] is a complex chronic inflammatory disease of the human gut with no clear aetiology. Traditionally, dysregulated adaptive immune responses play an important role even though accumulating evidence suggests a role also for innate immunity. Because of the well-known plasticity of γδ T cells, we investigated their percentage occurrence, phenotypic features and effector functions in the intestinal mucosa of early-onset and long-standing IBD patients, as compared to healthy subjects. Methods Fresh biopsies from 30 Crohn’s disease and ulcerative colitis patients were obtained and digested, and cells were analysed by flow cytometry. Resul…
Downregulation of miRNA17-92 cluster marks Vγ9Vδ2 T cells from patients with rheumatoid arthritis
2018
Abstract Background We aimed to evaluate the phenotype, function, and microRNA (miRNA)17–92 cluster expression in Vγ9Vδ2 T-cell subsets and the correlation with immune response in rheumatoid arthritis (RA) patients. Methods Peripheral blood from 10 early RA untreated patients and 10 healthy donors (HD) was obtained. Polyclonal Vγ9Vδ2 T-cell lines were generated and analysed by flow cytometry. Analysis of miRNA17–92 cluster expression was performed by real-time polymerase chain reaction (RT-PCR), and expression of mRNA target genes was also studied. Results A remarkable change in the distribution of Vγ9Vδ2 T-cell functional subsets was observed in the peripheral blood of RA patients compared…
Interleukin (IL)-9/IL-9R axis drives γδ T cells activation in psoriatic arthritis patients
2016
Summary Cytokines such as tumour necrosis factor (TNF)-α, interleukin (IL)-12, interferon (IFN)-γ, IL-23 and, more recently, IL-9, have been implicated in the initiation/maintenance of inflammation in psoriasis and psoriatic arthritis (PsA). In the present study we aimed to characterize the role of γδ T cells in peripheral blood and synovial fluid of PsA patients and to investigate their response to in-vitro stimulation with antigen or cytokines (IL-9 and IL-23). γδ T cells isolated from peripheral blood mononuclear cells and synovial fluid were analysed by flow cytometry to evaluate the phenotype and cytokine production. IL-23R and IL-9R gene expression were also evaluated by reverse trans…
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…
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…
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…