Search results for "Interferon gamma"
showing 10 items of 107 documents
The use of clonal mRNA as an antigenic format for the detection of antigen-specific T lymphocytes in IFN-gamma ELISPOT assays.
2003
Abstract Most assay systems for the quantification of antigen-specific T-cell responses in infectious, malignant and autoimmune disease depend on the peptide antigen format and are therefore restricted to known epitopes and their presenting HLA molecules. Here we tested in ELISPOT assays the application of in vitro-transcribed clonal mRNA as an alternative antigen format covering all potential epitopes of a given antigen. As model antigens, we chose pp65 of human cytomegalovirus (HCMV) and human tyrosinase (hTyr). Antigen-presenting cells (APC) were K562 cells stably transfected with single HLA class I alleles and autologous dendritic cells (DC). As effectors, we applied in vitro-generated …
Disruption of T helper 2-immune responses in Epstein–Barr virus-induced gene 3-deficient mice
2002
Epstein–Barr virus-induced gene 3 (EBI3) is a widely expressed IL-12p40-related protein that associates as a heterodimer with either IL-12p35 or an IL-12p35 homologue, p28, to create a new cytokine (IL-27). To define the function of EBI3in vivo, we generated knockout mice in which theebi3gene was targeted by homologous recombination. EBI3−/−mice exhibited normal numbers of both naive and mature CD4+and CD8+T cells and B cells, but markedly decreased numbers of invariant natural killer T cells (iNKT) as defined by staining with an α-galactosylceramide (αGalCer)-loaded CD1d-tetramer. iNKT cells from EBI3−/−mice exhibited decreased IL-4 and, to a lesser extent, IFN-γ production after αGalCer s…
Cytokine- and Interferon-Modulating Properties of Echinacea spp. Root Tinctures Stored at −20°C for 2 Years
2007
Echinacea spp. phytomedicines are popular for treating upper respiratory infections. The purpose of this investigation was to examine the immunomodulatory properties of Echinacea tinctures from seven species after being stored at -20 degrees C for 2 years. Two experimental techniques were employed using human peripheral blood mononuclear cells (PBMC). In the first set of experiments, PBMCs were stimulated in vitro with tinctures alone and assayed for proliferation and production of interleukin-10 (IL-10), IL-12, and tumor necrosis factor-alpha (TNF-alpha). In the second set of experiments, subjects were immunized with influenza vaccine. PBMCs from vaccinated individuals were stimulated in v…
Ambiguous Role of Interleukin-12 in Yersinia enterocolitica Infection in Susceptible and Resistant Mouse Strains
1998
ABSTRACT Endogenous interleukin-12 (IL-12) mediates protection against Yersinia enterocolitica in C57BL/6 mice by triggering gamma interferon (IFN-γ) production in NK and CD4 + T cells. Administration of exogenous IL-12 confers protection against yersiniae in Yersinia -susceptible BALB/c mice but exacerbates yersiniosis in resistant C57BL/6 mice. Therefore, we wanted to dissect the different mechanisms exerted by IL-12 during Yersinia infections by using different models of Yersinia -resistant and -susceptible mice, including resistant C57BL/6 mice, susceptible BALB/c mice, intermediate-susceptible wild-type 129/Sv mice, 129/Sv IFN-γ-receptor-deficient (IFN-γR −/− ) mice and C57BL/6 tumor n…
IFN-? in Candida albicans infections
2009
The dimorphic fungus Candida albicans is the most frequent etiologic agent that causes opportunistic infections called candidiasis, a disease whose systemic manifestation could prove fatal and whose incidence is increasing as a result of an expanding immunocompromised population. Here we review the role of interferon-gamma (IFN-gamma) in the host protection against invasive candidiasis. This cytokine plays an essential role in both the innate and adaptive arms of the immune response to candidiasis. We focus on recent progress on host-pathogen interactions at the molecular level, leading to the production of IFN-gamma by host cells. IFN-gamma is produced by CD4 Th1, CD8, gamma delta T, and n…
Interleukin-12 in Human Boutonneuse Fever Caused by Rickettsia conorii
2000
Interleukin (IL)-12 contributes to the resistance against a number of intracellular pathogens. We examined the potential biological role of IL-12 by studying peripheral blood mononuclear cells (PBMC), its production and its effect on cytokine synthesis in 20 Sicilian patients with boutonneuse fever (BF) caused by Rickettsia conorii. Data indicate that PBMC from acute BF patients were able to produce IL-12 in response to in vitro stimulation with rickettsial antigen (Ag): this production was higher than that detected in healed patients. Monocytes were the main source of IL-12 by PBMC from BF patients. IL-12 secretion by in vitro Ag-stimulated PBMC from BF patients was potentiated by recombin…
Interleukin-15, as Interferon-gamma, Induces the Killing of Leishmania infantum in Phorbol-Myristate-Acetate-Activated Macrophages Increasing Interle…
2004
The potential leishmanicidal activity of interleukin-15 (IL-15) was examined while priming with the cytokine phorbol-myristate-acetate (PMA)-activated macrophages and infecting them with Leishmania infantum parasites. The activation of macrophage cultures with IL-15 determined a significant anti-leishmanial activity, comparable with that induced by interferon-gamma (IFN-gamma). The killing of Leishmania in macrophages primed with IL-15, as well as with IFN-gamma, was followed by an increase in the IL-12 synthesis. The neutralization of IL-15 or IFN-gamma, by specific monoclonal antibodies (MoAb) caused a significant reduction in leishmanicidal activity. Furthermore, in PMA-activated macroph…
Effects of cytokines on synthesis and function of the hepatic asialoglycoprotein receptor
1994
In this study we have investigated whether cytokines, critical mediators of the immune response, might have a direct effect on the expression and/or function of the human hepatic asialoglycoprotein receptor (ASGPR). Binding and uptake of asialoglycoproteins by the human hepatoma cell line, HepG2, and by freshly isolated rat hepatocytes were inhibited by 50% after 3-6 hours and completely abolished following a 24 hour exposure to tumor necrosis factor (TNF) alpha, interferon (INF) alpha or gamma, or interleukin-2 (IL-2). The loss of ASGPR binding activity mediated by IL-2 was reversible up to 4 hours of exposure and accompanied by the selective phosphorylation of the cell-surface receptor. S…
Diagnóstico de la tuberculosis en la edad pediátrica. Documento de consenso de la Sociedad Española de Infectología Pediátrica (SEIP) y la Sociedad E…
2010
Resumen: La tuberculosis continúa siendo uno de los problemas sanitarios más importantes en el mundo. En países desarrollados se está asistiendo a un aumento de casos, incluidos los niños, por diferentes motivos. El más determinante parece ser la inmigración procedente de zonas con elevada endemia de tuberculosis.Es prioritario que se establezcan las medidas necesarias para optimizar el diagnóstico precoz y adecuado de las distintas formas clínicas de tuberculosis en niños. Para ello, la Sociedad Española de Infectología Pediátrica (SEIP) y la Sociedad Española de Neumología Pediátrica (SENP), ambas pertenecientes Asociación Española de Pediatría, han decidido realizar el presente documento…
The Inhibitory Effects of Prednisone, 16-Methylen-Prednisolone, and Acth on Con-A Induced Lymphokines (Interferon-Y) as Measured by the Chemiluminesc…
1988
When lymphocytes are stimulated with mitogens or antigens they are enhanced via a cascade of lymphokines to produce interferon-y (IFN-y). IFN-y augments the H2O2 secretion of human monocytes which indirectly can be measured by chemiluminescence. We tested prednisone, 16-methylen-prednisolone and ACTH for their effect to inhibit the Con-A induced stimulation of the chemiluminescence-activity. All three hormones inhibited significantly the stimulation: prednisone up to 52.5% (concentration = 150 micrograms/ml, p = 0.000005), 16-methylen-prednisolone up to 22.5% (concentration = 2.5 micrograms/ml, p = 0.006) and ACTH up to 33% (concentration = 10 micrograms/ml, p = 0.0036).