Search results for "Lymphocyte Subsets"
showing 10 items of 212 documents
NFATc2 and NFATc3 transcription factors play a crucial role in suppression of CD4+ T lymphocytes by CD4+ CD25+ regulatory T cells
2005
The phenotype of NFATc2(-/-) c3(-/-) (double knockout [DKO]) mice implies a disturbed regulation of T cell responses, evidenced by massive lymphadenopathy, splenomegaly, and autoaggressive phenomena. The population of CD4(+) CD25(+) T cells from DKO mice lacks regulatory capacity, except a small subpopulation that highly expresses glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) and CD25. However, neither wild-type nor DKO CD4(+) CD25(+) regulatory T cells (T reg cells) are able to suppress proliferation of DKO CD4(+) CD25(-) T helper cells. Therefore, combined NFATc2/c3 deficiency is compatible with the development of CD4(+) CD25(+) T reg cells but renders c…
Modifications of general parameters of immune activation in the sera of Sicilian patients with Boutonneuse fever
1998
SUMMARYThe serum levels of β2-microglobulin (β2-M), soluble HLA class I antigen (sHLA-I), soluble CD4 (sCD4) and CD8 (sCD8) were studied in 98 Sicilian patients with Boutonneuse fever (BF). In different stages of infection all markers were significantly increased in sera from Sicilian patients with acute BF compared with healthy controls. sCD8 and sHLA-I reached the peak in the second week after the onset of symptoms, whereas sCD4 and β2-M reached the peak in the first week. Afterwards sCD8 decreased to the levels of controls within the third week, the other parameters decreased later and were unmodified until the third week of infection. Significant correlations were found between sCD4 and…
A distinct subset of HLA-DR+-regulatory T cells is involved in the induction of preterm labor during pregnancy and in the induction of organ rejectio…
2010
Regulatory T cells (Tregs) are known to suppress alloimmune responses during pregnancy and post organ transplantation. We demonstrate that a distinct subset of FoxP3(+)DR(+)-Tregs among the total CD4(+)CD127(low+/-)CD25(+)-Treg cell pool is critically involved in preterm labor induction and kidney transplant rejection as well. Compared to healthy pregnancies and non-rejecting kidney recipients, we found that the percentage of the FoxP3(+)DR(+)-Treg subset was not reduced, but that the level of HLA-DR expression of such Tregs was strongly diminished in preterm laboring women and in patients with acute renal allograft rejection. In addition, both patient collectives showed a significantly red…
Increased PD-1 Expression and Altered T Cell Repertoire Diversity Predict Mortality in Patients with Septic Shock: A Preliminary Study
2017
Sepsis causes impairment of innate and adaptive immunity by multiple mechanisms, including depletion of immune effector cells and T cell exhaustion. Although lymphocyte dysfunction is associated with increased mortality and potential reactivation of latent viral infection in patients with septic shock, the relation between viral reactivation and lymphocyte dysfunction is obscure. The objectives of this study were 1) to determine the relation of lymphocyte dysfunction to viral reactivation and mortality, and 2) to evaluate recovery of lymphocyte function during septic shock, including T cell receptor (TCR) diversity and the expression of programmed death 1 (PD-1). In 18 patients with septic …
CD3ε Expression Defines Functionally Distinct Subsets of Vδ1 T Cells in Patients With Human Immunodeficiency Virus Infection
2018
Human γδ T cells expressing the Vδ1 T cell receptor (TCR) recognize self and microbial antigens and stress-inducible molecules in a major histocompatibility complex -unrestricted manner and are an important source of innate interleukin-17. Vδ1 T cells are expanded in the circulation and intestines of patients with human immunodeficiency virus (HIV) infection. In the present study, we show that patients with HIV have elevated frequencies, but not absolute numbers, of circulating Vδ1 T cells compared to control subjects. This increase was most striking in the patients with Candida albicans co-infection. Using flow cytometry and confocal microscopy, we identify two populations of Vδ1 T cells, …
Phenotypical analysis and cytokine release of liver-infiltrating and peripheral blood T lymphocytes from patients with chronic hepatitis of different…
2008
Cytokines released by infiltrating T cells may contribute to the hepatic injury in chronic hepatitis. Therefore, we characterized peripheral blood- and liver-infiltrating T cells from patients with chronic hepatitis of different etiology and determined the T cell phenotypes and the cytokine release. Liver tissue and peripheral blood-derived T cells from patients with autoimmune hepatitis and primary biliary cirrhosis predominantly expressed CD4-molecules and the alpha- and beta-chains of the T cell receptor (TCR). In chronic viral hepatitis B and C, liver- and blood-derived T cells were preferentially CD8+ T cells expressing the alpha beta TCR. Mitogenic stimulation with irradiated Daudi ly…
In the presence of IL-21 human cord blood T cells differentiate to IL-10-producing Th1 but not Th17 or Th2 cells.
2012
Abstract IL-21, a member of the IL-2 cytokine family, is mainly produced by activated CD4+ T cells and controls the activity of immune and also non-immune cells. As a pleiotropic cytokine, IL-21 acts on both innate and adaptive immune responses, suggesting that IL-21 may be a master regulator of the T-cell-dependent adaptive immune response. Although IL-21 is described as mostly promoting inflammation, evidence also suggests inhibitory effects of IL-21. However, its role, particularly in the human neonatal immune system, has not been detailed so far. Here, we assessed the effect of IL-21 in the specific context of the neonatal immune response and delineated differences between the human new…
Treatment of COVID-19 with MSCs: how does it work?
2021
The infusion of coronavirus disease 2019 (COVID-19) patients with mesenchymal stem cells (MSCs) potentially improves clinical symptoms, but the underlying mechanism remains unclear. We conducted a randomized, single-blind, placebo-controlled (29 patients/group) phase II clinical trial to validate previous findings and explore the potential mechanisms. Patients treated with umbilical cord-derived MSCs exhibited a shorter hospital stay (P = 0.0198) and less time required for symptoms remission (P = 0.0194) than those who received placebo. Based on chest images, both severe and critical patients treated with MSCs showed improvement by day 7 (P = 0.0099) and day 21 (P = 0.0084). MSC-treated pat…
Effect of isoprinosine on IL-2, IFN-γ and IL-4 production in vivo and in vitro
1991
The effects of an immunopotentiating drug, isoprinosine, on the splenocytes of BALB/c mice to produce cytokines were investigated. Isoprinosine enhanced IL-2 production, upregulating the expression of IL-2 receptor in vitro. It also significantly increased the IFN-gamma secretion and decreased the IL-4 production in vivo. The significance of these findings in terms of immune regulation is discussed.
The role of recent thymic emigrant-regulatory T-cell (RTE-Treg) differentiation during pregnancy.
2014
During pregnancy, regulatory T cells (Tregs) have a key role in maternal immune tolerance to the semi-allogeneic fetus. Our previous results showed that the naive CD45RA(+)-Treg pool is functionally improved in pregnant women compared with non-pregnant women. Therefore, we examined the thymic output and differentiation of CD45RA(+)CD31(+) recent thymic emigrant (RTE)-Tregs during normal pregnancy and in the presence of preeclampsia. With the onset of pregnancy, the composition of the total CD4(+)CD127(low+/-)FoxP3(+)-Treg pool changed in the way that its percentage of RTE- and CD45RA(-)CD31(+)-memory Tregs decreased strongly, whereas that of the CD45RA(+)CD31(-)-mature naive (MN)-Tregs did …