Search results for " subsets."
showing 6 items of 216 documents
Changes in lymphocyte subsets after cardiac surgery in children.
2001
Children undergoing cardiopulmonary bypass (CPB) operations have an increased risk of developing severe infections. Impairment of the immune system may contribute to the development of sequelae such as capillary leaks, pulmonary dysfunction and auto-immune reactions. The objective of this study was to investigate the impact of cardiac surgery with CPB on the immune system of infants and young children. We conducted a prospective study to investigate the changes in circulating lymphocyte subpopulations in a sample of 21 consecutive infants and young children undergoing cardiac surgery for congenital heart disease. The following statistically significant (P<0.05) results were obtained: leucoc…
Distinct subsets of regulatory T cells during pregnancy: is the imbalance of these subsets involved in the pathogenesis of preeclampsia?
2008
Abstract Regulatory T cells (CD4 + CD25 + FoxP3 + -Treg cells) are important regulators of tolerance induction during pregnancy. We now found that the number of CD4 + CD25 + FoxP3 + -Treg cells decreases during normal course of pregnancy and even more so in women affected by preeclampsia. The functional activity of these CD4 + CD25 + -Treg cells was significantly reduced in comparison to those of healthy pregnants. Further analysis revealed two Treg subsets that differed with regard to the FoxP3 and CD25 expression. The percentage of both, CD4 + CD25 + FoxP3 high+ -Treg and CD4 + CD25 high+ FoxP3 + , was maximal in the first and second trimenon, but declined severely in the third trimenon. …
Small for gestational age (SGA) neonates show reduced suppressive activity of their regulatory T cells
2009
Little information exists concerning the role of fetal regulatory T cells (Tregs) during intrauterine development. We examined whether complications such as reduced birth weight or the occurrence of preterm labor were associated with deficiencies in the number or in the immunosuppressive activity of Tregs in the fetal circulation. Their total number did not change during normal or complicated pregnancy. In contrast, their level of FoxP3 expression decreased continuously with gestational age and was significantly reduced in the presence of spontaneous term, but not preterm labor. In small for gestational age (SGA) neonates, FoxP3 expression was constantly decreased when compared to age match…
Modulation of IL-2, IFN-γ, TNF-α and IL-4 production in mice of different ages by thymopentin
1992
The effect of an immunomodulator drug thymopentin (TP5) on the production of various cytokines (IFN-gamma, IL-2, IL-4, TNF-alpha) in mice of different ages has been studied. TP5 enhanced IL-2, TNF-alpha and IFN-gamma production but reduced the IL-4 secretion by splenocytes from aged mice (greater than 120 week old) in vitro. However, it had no effect on the IL-2, IFN-gamma, TNF-alpha or IL-4 production by splenocytes from young and adult mice. TP5 injected subcutaneously was able to induce high levels of IL-2 production by splenocytes from all groups of mice. The TP5 effect on TNF-alpha and IFN-gamma was similar, even though it was significant only in old mice. Furthermore, TP5 was able to …
IL-27 controls the development of inducible regulatory T cells and Th17 cells via differential effects on STAT1
2007
IL-27 is an IL-12-related cytokine frequently present at sites of inflammation that can promote both anti- and pro-inflammatory immune responses. Here, we have analyzed the mechanisms how IL-27 may drive such divergent immune responses. While IL-27 suppressed the development of proinflammatory Th17 cells, a novel role for this cytokine in inhibiting the development of anti-inflammatory, inducible regulatory T cells (iTreg) was identified. In fact, IL-27 suppressed the development of adaptive, TGF-beta-induced Forkhead box transcription factor p3-positive (Foxp3(+)) Treg. Whereas the blockade of Th17 development was dependent on the transcription factor STAT1, the suppression of iTreg develo…
Differential requirements for antigen or homeostatic cytokines for proliferation and differentiation of human Vgamma9Vdelta2 naive, memory and effect…
2005
We have compared four human subsets of Vgamma9Vdelta2 T cells, naive (T(naive), CD45RA(+)CD27(+)), central memory (T(CM), CD45RA(-)CD27(+)), effector memory (T(EM), CD45RA(-)CD27(-)) and terminally differentiated (T(EMRA), CD45RA(+)CD27(-)), for their capacity to proliferate and differentiate in response to antigen or homeostatic cytokines. Cytokine responsiveness and IL-15R expression were low in T(naive) cells and progressively increased from T(CM) to T(EM) and T(EMRA) cells. In contrast, the capacity to expand in response to antigen or cytokine stimulation showed a reciprocal pattern and was associated with resistance to cell death and Bcl-2 expression. Whereas antigen-stimulated cells a…