Differential effects of asymptomatic Ascaris lumbricoides, Schistosoma mansoni or hook worm infection on the frequency and TGF-beta-producing capacity of regulatory T cells during active tuberculosis

Regulatory T cells (Tregs) are key players in the regulation of inflammatory responses. In this study, two natural molecules, namely, sparteine sulfate (SS) and harpagoside (Harp), were investigated for their ability to induce Tregs in human peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from healthy volunteers and grown in the presence or absence of ConA, with TGF-beta, SS or Harp. Expression of the mRNA of FoxP3, TGF-beta, IL-10 and GAPDH was assessed via q-PCR. The expression of Treg markers including CD4, CD25, CD127 and FoxP3 was measured via flow cytometry. The secretion of IL-10 and TGF-beta by cultured cells was assessed by ELISA. Furthermore, the suppressive role of SS and Harp on PBMCs in vitro was tested via allogeneic mixed lymphocyte reaction (MLR). Data obtained show that both compounds increased the expression of FoxP3, TGF-beta and IL-10 mRNA in resting PBMCs but to a lesser extent in activated cells. Moreover, they significantly increased the percent of CD4+CD25+FoxP3+CD127− Tregs in activated and naïve PBMCs. Functionally, both compounds caused a significant reduction in the stimulation index in allogeneic MLR. Together, our data demonstrate for the first time that SS and Harp can induce human Tregs in vitro and therefore have great potential as anti-inflammatory agents.

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Differential effects of α4β7 and GPR15 on homing of effector and regulatory T cells from patients with UC to the inflamed gut in vivo

Gut ◽

10.1136/gutjnl-2015-310022 ◽

2015 ◽

Vol 65 (10) ◽

pp. 1642-1664 ◽

Cited By ~ 67

Author(s):

Anika Fischer ◽

Sebastian Zundler ◽

Raja Atreya ◽

Timo Rath ◽

Caroline Voskens ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Differential Effects

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Dendritic Cell-Induced T Cell Non-Responsiveness Is Mediated by FOXP3+ and TGF-beta+IL-10+ CD4+ T Cells.

Blood ◽

10.1182/blood.v108.11.3891.3891 ◽

2006 ◽

Vol 108 (11) ◽

pp. 3891-3891

Author(s):

Zwi N. Berneman ◽

Nathalie Cools ◽

Viggo F.I. Van Tendeloo ◽

Marc Lenjou ◽

Griet Nijs ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Regulatory T Cells ◽

T Cell Activation ◽

Cd4 T Cells ◽

Cell Activation ◽

T Cell Immunity ◽

Tgf Beta ◽

Cell Immunity

Abstract Dendritic cells (DC), the professional antigen presenting cells of the immune system, exert important functions both in induction of T cell immunity as well as of tolerance. Previously, it was accepted that the main function of immature DC (iDC) in their in vivo steady state condition is to maintain peripheral tolerance to self-antigens and that these iDC mature upon encounter of so-called danger signals and subsequently promote T cell immunity. However, a growing body of experimental evidence now indicates that traditional DC maturation can no longer be used to distinguish between tolerogenic and immunogenic properties of DC. In this study, we compared the in vitro stimulatory capacity of immature DC (iDC), cytokine cocktail-matured DC (CC-mDC) and poly I:C-matured DC (pIC-mDC) in the absence and presence of antigen. All investigated DC types could induce at least 2 subsets of regulatory T cells. We observed a significant increase in both the number of functionally suppressive transforming growth factor (TGF)-beta+ interleukin (IL)-10+ T cells as well as of CD4+CD25+FOXP3+ T cells within DC/T cell co-cultures as compared to T cell cultures without DC. The induction of these regulatory T cells correlates with in vitro T cell non-responsiveness after co-culture with iDC and CC-mDC, while stimulation with pIC-mDC resulted in reproducible cytomegalovirus pp65 or influenza M1 matrix peptide-specific T cell activation as compared to control cultures in the absence of DC. In addition, the T cell non-responsiveness after stimulation with iDC was shown to be mediated by TGF-beta and IL-10. Moreover, the suppressive capacity of CD4+ T cells activated by iDC and CC-mDC was shown to be transferable when these CD4+ T cells were added to an established T cell response. In contrast, addition of CD4+ T cells stimulated by pIC-mDC made responder T cells refractory to their suppressive activity. In conclusion, we hypothesize that DC have a complementary role in inducing both regulatory T cells and effector T cells, where the final result of antigen-specific T cell activation will depend on the activation state of the DC. This emphasizes the need for proper DC activation when T cell immunity is the desired effect, especially when used in clinical trials.

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