Search results for "T cell"

Characterization of N-glycosylated receptors for the tobacco lectin in the plant cell nucleus

2008

P574Activation of the regulatory T-cell-indoleamine 2,3 dioxygenase Axis promotes vascular tolerance mechanisms and reduces atherosclerosis

2018

Protection against autoimmunity is driven by thymic epithelial cell–mediated regulation of Tregdevelopment

2021

Medullary thymic epithelial cells (mTECs) are key antigen-presenting cells mediating T cell tolerance to prevent harmful autoimmunity. mTECs both negatively select self-reactive T cells and promote...

Dependence of T-lymphocyte activation on the extent of cellular damage

2010

Mechanically damaged cells release intracellular substances, resulting in the activation of CD4- and CD8-positive T-lymphocytes. The goal of this investigation was to quantify and compare fractions of activated CD4- and CD8-positive T-lymphocytes, based on the quantity of damaged cells in a given blood sample. Blood samples were mechanically stressed by vortexing intensely. Subsequently, different quantities of distressed blood samples were mixed with samples of fresh, whole blood. Afterwards, the extent of CD4- and CD8-positive T-cell activation was examined in the mixture by flow cytometry. Sine-like curves of T-cell activation were observed for both CD4- (T-helper mediated) and CD8- (cyt…

B and T cell immune responses elicited by the BNT162b2 (Pfizer–BioNTech) COVID-19 vaccine in nursing home residents

2021

ABSTRACTObjectivesThe immunogenicity of the BNT162b2 COVID-19 vaccine is understudied in elderly people with comorbidities. We assessed SARS-CoV-2-S-targeted antibody and T cell responses following full vaccination in nursing home residents (NHR).MethodsWe recruited 60 NHR (44 female; median age, 87.5 years), of whom 10 had previously had COVID-19, and 18 healthy controls (15 female; median age, 48.5 years). Pre- and post-vaccination blood specimens were available for quantitation of total antibodies binding RBD and enumeration of SARS-CoV-2-S-reactive IFN-γ CD4+ and CD8+ T cells by flow cytometry.ResultsThe seroconversion rate in presumably SARS-CoV-2 naïve NHR (95.3%), either with or with…

SAT0025 MIR 106A, MIR 19A-B, MIR 20A and MIR21A regulate vγ9vδ2 functions participating in the inflammatory responses occurring in rheumatoid arthrit…

2017

Background miRNAs are non-coding RNAs which have significant roles in regulating gene expression. The miR17-92 cluster appears to be a key factor in the inflammatory pathways activated during RA. Objectives In this study we aimed to evaluate miR17–92 expression and functions in γδ T cell subsets in RA patients, γδ T cells, in fact produce proinflammatory cytokines such as IFN-g, IL-6 and IL-8 that may contribute to the inflammatory responses in RA. Methods Heparinized peripheral blood from 10 early RA untreated patients and 10 healthy donors was obtained for this study. Polyclonal Vγ9Vδ2 T cell lines were generated first by magnetic isolation followed by sorting (FACSAria) and further analy…

Lymphocytes from hepatic inflammatory infiltrate kill rat hepatocytes in primary culture

1990

In the last few years it has become possible in the liver to isolate lymphocytes from inflammatory infiltrates and to culture them in vitro. Most of the lymphocyte clones obtained are CD 8 + cytotoxic cells, but interactions between these lymphocytes and hepatocytes in primary culture have not been analysed previously. In this study, cloned human T lymphocytes from liver biopsies and from the peripheral blood of patients with chronic hepatitis B or primary biliary cirrhosis, after phenotypical and functional characterization into CD 8+ or CD 4+ cytotoxic lymphocytes, were activated in an antigen-independent fashion by adding either anti CD 3 or anti CD 2/R-3 monoclonal antibodies to the cel…

Cytotoxic effects of Jay Amin hydroxamic acid (JAHA), a ferrocene-based class I histone deacetylase inhibitor, on triple-negative MDA-MB231 breast ca…

2012

The histone deacetylase inhibitors (HDACis) are a class of chemically heterogeneous anticancer agents of which suberoylanilide hydroxamic acid (SAHA) is a prototypical member. SAHA derivatives may be obtained by three-dimensional manipulation of SAHA aryl cap, such as the incorporation of a ferrocene unit like that present in Jay Amin hydroxamic acid (JAHA) and homo-JAHA [ Spencer , et al. ( 2011 ) ACS Med. Chem. Lett. 2 , 358 - 362 ]. These metal-based SAHA analogues have been tested for their cytotoxic activity toward triple-negative MDA-MB231 breast cancer cells. The results obtained indicate that of the two compounds tested, only JAHA was prominently active on breast cancer cells with a…

Synthesis and biological evaluation of sphingosine kinase 2 inhibitors with anti-inflammatory activity.

2019

The synthesis of inhibitors of SphK2 with novel structural scaffolds is reported. These compounds were designed from a molecular modeling study, in which the molecular interactions stabilizing the different complexes were taken into account. Particularly interesting is that 7‐bromo‐2‐(2‐phenylethyl)‐2,3,4,5‐tetrahydro‐1,4‐epoxynaphtho[1,2‐b]azepine, which is a selective inhibitor of SphK2, does not exert any cytotoxic effects and has a potent anti‐inflammatory effect. It was found to inhibit mononuclear cell adhesion to the dysfunctional endothelium with minimal impact on neutrophil–endothelial cell interactions. The information obtained from our theoretical and experimental study can be us…

Liver cell damage caused by monoclonal antibody against an organ-specific membrane antigen in vivo and in vitro

1987

Summary Monoclonal antibodies have been raised against different antigenic determinants of normal rabbit hepatocytes. One antibody (2D3) recognized a liver-specific 43 kDa protein displayed exclusively on the basolateral portion of the hepatocellular membrane. Purified monoclonal antibodies were injected intravenously into rabits. Following the injection of antibody 2D3, a dose-dependent increase of liver enzyme activities in sera was observed. Within 8 h, marked morphological alterations of the hepatocytes, including multiple cell necroses, could be demonstrated by light and electron microscopy. When isolated vital rabbit hepatocytes in culture were used as targets, cytotoxic effects of th…