Search results for "Immune system"
showing 10 items of 2885 documents
Intracellular Cytokine Staining and Flow Cytometry: Considerations for Application in Clinical Trials of Novel Tuberculosis Vaccines.
2015
Intracellular cytokine staining combined with flow cytometry is one of a number of assays designed to assess T-cell immune responses. It has the specific advantage of enabling the simultaneous assessment of multiple phenotypic, differentiation and functional parameters pertaining to responding T-cells, most notably, the expression of multiple effector cytokines. These attributes make the technique particularly suitable for the assessment of T-cell immune responses induced by novel tuberculosis vaccines in clinical trials. However, depending upon the particular nature of a given vaccine and trial setting, there are approaches that may be taken at different stages of the assay that are more s…
Tumour necrosis factor (TNF) production by T cell receptor-primed T lymphocytes is a target for low dose methotrexate in rheumatoid arthritis
1999
SUMMARYMethotrexate (MTX) is an effective immunosuppressive agent in various chronic inflammatory diseases such as rheumatoid arthritis (RA). However, its mechanisms of action are only partially understood. In this study, we assessed the effects of MTX on the differentiation of peripheral blood (PB) CD4+CD45RA ‘naive’ and CD4+CD45RO ‘memory’ T cells from healthy controls and patients with RA. Accordingly, purified T cells were primed and restimulated in vitro via the T cell receptor (TCR) in the presence of IL-2 to generate effector T cells secreting large amounts of Th1 and Th2 cytokines. We observed that low doses of MTX strongly suppress TNF and to a lesser extent interferon-gamma (IFN-γ…
Management and long-term follow-up of early stage H. pylori-associated gastric MALT-lymphoma in clinical practice: An Italian, multicentre study
2009
Abstract Background/Aim Data on management and long-term follow-up of Helicobacter pylori -associated MALT-lymphoma in clinical practice are scanty. We evaluate the long-term efficacy of H. pylori eradication on low-grade MALT-lymphoma, and the efficacy of further therapies in refractory patients. Methods This study enrolled patients with stages I–II 1 MALT-lymphoma and H. pylori infection. H. pylori eradication was attempted in all patients. Patients with lymphoma persistence or progression following H. pylori treatments received further lymphoma treatments. Both 5-year and disease-free survivals were calculated. Results Sixty patients (stage I/II 1 : 50/10) were followed up for a median t…
LOW-DOSE INTERLEUKIN-2 INDUCES SYSTEMIC IMMUNE RESPONSES AGAINST HBsAg IN IMMUNODEFICIENT NON-RESPONDERS TO HEPATITIS B VACCINATION
1989
Abstract A metabolic monocyte defect appears to correlate with non-responsiveness to hepatitis B vaccine in many patients on haemodialysis. This defect prevents production of interleukin-2 during T-cell activation after antigen contact. Receptors for interleukin-2 are, however, expressed in greater numbers than in healthy subjects or uraemic responders to hepatitis B vaccination. In this study, ten uraemic patients, previous non-responders to vaccination against hepatitis B, were revaccinated with the same vaccine combined with one intramuscular injection (2·5 × 10 5 U) of natural human interleukin-2. Systemic production of antibodies against hepatitis B surface antigen was initiated in tho…
Predominance of Th1-type T cells in synovial fluid of patients with Yersinia-induced reactive arthritis
1992
The pathogenetic mechanisms underlying the development of reactive arthritis and the functional capacities of synovial T cells specific for Yersinia enterocolitica are still unclear. In this study we have determined the cytokine secretion patterns of 24 CD4+ synovial fluid (SF)-derived T cell clones from 2 patients with Yersinia-induced reactive arthritis, 16 clones specific for different Yersinia antigens and 8 clones as controls. The clones specific for Yersinia antigens predominantly belong to the T helper cell 1 (Th1) subset with production of interferon (IFN)-gamma and interleukin (IL)-2, but no IL-4, whereas SF T cells not reactive with Yersinia antigens produce IL-2, IL-4 and IFN-gam…
Differentiation, phenotype, and function of interleukin-17-producing human Vγ9Vδ2 T cells.
2011
Abstract In healthy adults, the major peripheral blood γδ T-cell subset expresses the Vγ9Vδ2 TCR and displays pleiotropic features. Here we report that coculture of naive Vγ9Vδ2 T cells with phosphoantigens and a cocktail of cytokines (IL-1-β, TGF-β, IL-6, and IL-23), leads to selective expression of the transcription factor RORγt and polarization toward IL-17 production. IL-17+ Vγ9Vδ2 T cells express the chemokine receptor CCR6 and produce IL-17 but neither IL-22 nor IFN-γ; they have a predominant terminally differentiated (CD27−CD45RA+) phenotype and express granzyme B, TRAIL, FasL, and CD161. On antigen activation, IL-17+ Vγ9Vδ2 T cells rapidly induce CXCL8-mediated migration and phagocy…
Static magnetic fields generated by a 0.5T MRI unit affects in vitro expression of activation markers and interleukin release in human peripheral blo…
2001
To investigate the effects of the static magnetic field (SMF) generated by a 0.5 T superconducting MRI unit on in vitro activation marker expression and interleukin release in human peripheral blood mononuclear cell (PBMC) samples from healthy volunteers.PBMC samples were split into two groups: exposed and sham-exposed under isothermal conditions. PBMC were exposed for 2 h at 24 degrees C to the SMF of a 0.5 T superconducting MRI unit. Immediately after exposure, both samples were cultured for 24 h at 37 degrees C with or without mitogenic stimulation by phytohaemagglutinin (PHA). PBMC were examined for expression of CD25, CD69 and CD71 by immunofluorescence analysis and supernatants were a…
A novel role of the CX3CR1/CX3CL1 system in the cross-talk between chronic lymphocytic leukemia cells and tumor microenvironment
2011
Several chemokines/chemokine receptors such as CCR7, CXCR4 and CXCR5 attract chronic lymphocytic leukemia (CLL) cells to specific microenvironments. Here we have investigated whether the CX(3)CR1/CX(3)CL1 axis is involved in the interaction of CLL with their microenvironment. CLL cells from 52 patients expressed surface CX(3)CR1 and CX(3)CL1 and released constitutively soluble CX(3)CL1. One third of these were attracted in vitro by soluble CX(3)CL1. CX(3)CL1-induced phosphorylation of PI3K, Erk1/2, p38, Akt and Src was involved in induction of CLL chemotaxis. Leukemic B cells upregulated CXCR4 upon incubation with CX(3)CL1 and this was paralleled by increased chemotaxis to CXCL12. Akt phosp…
Immunophenotypical comparison of Gaucher's and pseudo-Gaucher cells.
1996
An immunohistochemical study on bone marrow biopsies and spleens of patients with Gaucher's disease and chronic myeloid leukemia was performed to investigate the immunophenotype of Gaucher's cells and pseudo-Gaucher cells. A panel of antibodies was used which were reactive on paraffin-embedded tissues and directed against different hematopoietic lineage cells. Gaucher's cells and pseudo-Gaucher cells expressed a very similar immunophenotype and displayed an intense reaction for the monocytic antibodies tested, thus confirming their common origin and that they belong to the same system. The expression of HLA-DR antigens was much stronger in Gaucher's than in pseudo-Gaucher cells. This last f…
Differential regulation of Fas-mediated apoptosis in both thyrocyte and lymphocyte cellular compartments correlates with opposite phenotypic manifest…
2001
Several mechanisms are probably involved in determining the evolution of autoimmune thyroid disease (AITD) towards either hypothyroidism and the clinical syndrome known as Hashimoto's thyroiditis (HT) or toward hyperthyroidism and the symptoms of Graves' disease (GD). To gain further insight into such mechanisms we performed an exhaustive comparative analysis of the expression of key molecules regulating cell death (Fas, Fas ligand [FasL], Bcl-2) and apoptosis in both thyrocytes and thyroid infiltrating lymphocytes (TILs) from patients with either GD or HT. GD thyrocytes expressed less Fas/FasL than HT thyrocytes, whereas GD TILs had higher levels of Fas/FasL than HT TILs. GD thyrocytes exp…