Search results for "Concanavalin A"
showing 4 items of 94 documents
Effects of Mancozeb and Metribuzin on in vitro proliferative responses and oxidative stress of human and rat spleen lymphocytes stimulated by mitogens
2011
Pesticides have been shown to possess marked immunotropic activity. The aim of this work was to study the in vitro effects of different concentrations (1-100 µM) of Mancozeb (fungicide) and Metribuzin (herbicide), on the proliferative responses of human and rat spleen lymphocytes stimulated by concanavalin A (ConA, mitogen), the Th1- (IL-2, INFγ) and Th2- (IL-4) cytokine secretion and on the intracellular oxidative status. The results showed that Mancozeb significantly reduced ConA lymphocyte proliferation in a dose-dependent manner in both humans and rats. It also decreased IL-2, INFγ and IL-4 secretion with a a shift away to Th1 phenotype. Metribuzin at low concentrations (1-10 µM) result…
n-3 Fatty Acids Modulate T-Cell Calcium Signaling in Obese Macrosomic Rats
2004
Objective: We investigated the effects of a diet containing EPAX-7010, rich in PUFAs such as eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)], i.e., a PUFA/EPAX regimen, on T-cell activation in diabetic pregnant rats and their obese pups. Research Methods and Procedures: Mild hyperglycemia in pregnant rats was induced by intraperitoneal injection of streptozotocin on Day 5 of gestation. T-cell blastogenesis was assayed by using 3H-thymidine, whereas intracellular free calcium concentrations ([Ca2+]i) were measured by using Fura-2 in diabetic pregnant rats and their obese offspring. Results: Concavalin-A-stimulated T-cell proliferation was decreased in both pregnant dia…
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).
Production of functional IL-18 by different subtypes of murine and human dendritic cells (DC): DC-derived IL-18 enhances IL-12-dependent Th1 developm…
1998
IL-18 is a recently described cytokine that shares biological activities with IL-12 in driving the development of Th1-type T cells. As dendritic cells (DC) are very potent inducers of T cell proliferation and differentiation we wondered whether they utilize IL-18 as a factor driving Th1 development. We demonstrate by Northern blot and reverse transcription-PCR that various subtypes of human and murine DC as well as the DC-line XS contain IL-18 mRNA. When supernatants of either enriched Langerhans cells (LC) or bone marrow-derived DC were analyzed for production of IL-18 protein, IL-18 production was detected in an IL-18-specific ELISA. To assess whether the IL-18 protein released by DC is f…