Search results for " t-lymphocytes"
showing 10 items of 495 documents
Tumor infiltration by T lymphocytes expressing chemokine receptor 7 (CCR7) is predictive of favorable outcome in patients with advanced colorectal ca…
2011
Abstract Purpose: An efficient adaptive immunity is critical for a longer survival in cancer. We investigated the prognostic value of tumor infiltration by CD8+ T cells expressing the chemokine-receptor-7 (Tccr7) and the correlation between tumor infiltration by Tccr7 and regulatory CD4+FoxP3+ T cells (Treg) in 76 metastatic colorectal cancer (mCRC) patients enrolled in a phase III trial. Experimental Design: Tccr7 and Treg cell infiltration in tumor samples was quantified by immunohistochemistry. The correlation among Tccr7, Treg tumor infiltration, and patients' outcome was evaluated. Results: High Tccr7 tumor infiltration was predictive of prolonged OS [high vs. low Tccr7 score: median 3…
Mast cells as rapid innate sensors of cytomegalovirus by TLR3/TRIF signaling-dependent and -independent mechanisms
2014
The succinct metaphor, ‘the immune system's loaded gun', has been used to describe the role of mast cells (MCs) due to their storage of a wide range of potent pro-inflammatory and antimicrobial mediators in secretory granules that can be released almost instantly on demand to fight invaders. Located at host–environment boundaries and equipped with an arsenal of pattern recognition receptors, MCs are destined to be rapid innate sensors of pathogens penetrating endothelial and epithelial surfaces. Although the importance of MCs in antimicrobial and antiparasitic defense has long been appreciated, their role in raising the alarm against viral infections has been noted only recently. Work on cy…
Identical T-cell expansions in the colon mucosa and the synovium of a patient with enterogenic spondyloarthropathy.
2000
Abstract Intestinal T lymphocytes activated by antigen are suspected to play a key role in enterogenic spondyloarthropathies (SpA). Therefore, we aimed to identify and functionally characterize T-cell clones that are coexpanded in the intestinal mucosa and the synovium. Colon, peripheral blood, and synovium of a patient with enterogenic SpA were screened for clonal T-cell expansions by TCRB-CDR3 length analysis and sequencing. T-cell clones expanded in vivo were isolated from archived synovial cells by targeted T-cell cloning and characterized for phenotype, cytokine production, and antigen specificity. The synovial TCRBV18 + T-cell repertoire of the patient was dominated by 2 CD8 + T-cell …
Effect of cytomegalovirus-induced immune response, self antigen-induced immune response, and microbial translocation on chronic immune activation in …
2013
International audience; We evaluated the impact of cytomegalovirus (CMV)-induced immune responses, autoimmune-induced immune responses, and microbial translocation on immune activation in 191 human immunodeficiency virus type 1-infected patients from the ANRS CO3 Aquitaine Cohort. All enrolled subjects had achieved long-term virological suppression during receipt of combination antiretroviral therapy (cART). HLA-DR(+)/CD38(+) expression was 16.8% among CD8(+) T cells. Independent of age, CD4(+) T-cell count, 16S ribosomal DNA load, and regulatory T-cell count, positive results of Quantiferon CMV analysis (P = .02), positive results of CMV-pp65 enzyme-linked immunosorbent spot analysis (P = …
Analysis of Mycobacterium tuberculosis-Specific CD8 T-Cells in Patients with Active Tuberculosis and in Individuals with Latent Infection
2009
CD8 T-cells contribute to control of Mycobacterium tuberculosis infection, but little is known about the quality of the CD8 T-cell response in subjects with latent infection and in patients with active tuberculosis disease. CD8 T-cells recognizing epitopes from 6 different proteins of Mycobacterium tuberculosis were detected by tetramer staining. Intracellular cytokines staining for specific production of IFN-gamma and IL-2 was performed, complemented by phenotyping of memory markers on antigen-specific CD8 T-cells. The ex-vivo frequencies of tetramer-specific CD8 T-cells in tuberculous patients before therapy were lower than in subjects with latent infection, but increased at four months a…
No pol mutation is associated independently with the lack of immune recovery in patients infected with HIV and failing antiretroviral therapy
2011
An investigation was undertaken to determine whether specific pol mutations hinder long-term immune recovery regardless of virological response. In total, 826 patients with >50 HIV RNA copies/ml, who underwent genotypic resistance testing between 1 January 2000 and 31 December 2003 after >3 years of antiretroviral treatment, and were followed up for >3 years after genotypic resistance testing, were analyzed retrospectively. The outcome of the study was the lack of immune recovery after >3 years of follow-up, defined as a slope by linear regression 50 copies/ml divided by the number of HIV RNA measurements during follow-up. Logistic regression was used for univariable and multivariable analy…
Reciprocal stimulation of gammadelta T cells and dendritic cells during the anti-mycobacterial immune response.
2004
Gammadelta T cells and dendritic cells (DC) are two distinct cell types of innate immunity that participate in early phases of immune response against Mycobacterium tuberculosis infection. Here we show that a close functional relationship exists between these cell populations. Using an in vitro coculture system, Vgamma1 T cells from Tcrb(-/- )mice were found to be activated by DC infected in vitro with BCG, as indicated by the elevated CD69 expression, IFN-gamma secretion and cytotoxic activity. This activation process was due to a non-cognate mechanism since it required neither cell to cell contact nor interaction between the TCR and a specific antigen, but was mediated by DC-derived IL-12…
In vitro anticholinergic drugs affect CD8+ peripheral blood T-cells apoptosis in COPD
2011
Novel pharmacological strategies are aimed at the resolution of systemic inflammation in COPD potentiating peripheral blood T-cell (PBT-cell) apoptosis. Although muscarinic acetylcholine receptors (mAChRs) M(3) and choline-acetyltransferase (ChAT) participate in the airway inflammation of COPD, their role in PBT-cell apoptosis remains unexplained. We evaluated in PBT-cells from COPD patients, smoker (S) and control (C) subjects: (1) apoptosis (by annexin V binding), (2) mAChR M(3) and ChAT expression, acetylcholine (ACh)-binding; (3) choline levels in serum and PBT-cells extracts. We tested the effects of Tiotropium (Spiriva(®)) and hemicholinium-3 (HCh-3) on apoptosis, NFκB pathway, caspas…
Protective role of nuclear factor of activated T cells 2 in CD8+ long-lived memory T cells in an allergy model
2007
Background The transcriptional regulation of cytokines released and controlled by memory T cells is not well understood. Defective IFN-γ production in allergic asthma correlates in human beings with the risk of wheezing in childhood. Objective To understand the role of the transcription factor nuclear factor of activated T cells 2 (NFATc2) in memory and effector T cells in the airways in experimental allergic asthma. Methods We used murine models of allergic asthma and adoptive cell transfer of fluorescence-activated sorted cells in a disease model. Results Mice lacking NFATc2 developed an increase in airway hyperresponsiveness (AHR), remodeling, and serum IgE levels on ovalbumin sensitizat…
Human CD8+ T-cells Recognizing Peptides from Mycobacterium tuberculosis (Mtb) Presented by HLA-E Have an Unorthodox Th2-like, Multifunctional, Mtb In…
2015
Mycobacterial antigens are not exclusively presented to T-cells by classical HLA-class Ia and HLA-class II molecules, but also through alternative antigen presentation molecules such as CD1a/b/c, MR1 and HLA-E. We recently described mycobacterial peptides that are presented in HLA-E and recognized by CD8+ T-cells. Using T-cell cloning, phenotyping, microbiological, functional and RNA-expression analyses, we report here that these T-cells can exert cytolytic or suppressive functions, inhibit mycobacterial growth, yet express GATA3, produce Th2 cytokines (IL-4,-5,-10,-13) and activate B-cells via IL-4. In TB patients, Mtb specific cells were detectable by peptide-HLA-E tetramers, and IL-4 and…