Sub-lethal ionizing radiation alters Foxp3 expression in CD4+ T regulatory (Treg) cells in vitro and in vivo

TGF-β-induced regulatory T cells (iTregs) retain Foxp3 expression and immune-suppressive activity in collagen-induced arthritis (CIA). However, the mechanisms whereby transferred iTregs suppress immune responses, particularly the interplay between iTregs and dendritic cells (DCs)in vivo, remain incompletely understood. In this study, we found that after treatment with iTregs, splenic CD11c+DCs, termed “DCiTreg,” expressed tolerogenic phenotypes, secreted high levels of IL-10, TGF-β, and IDO, and showed potent immunosuppressive activityin vitro. After reinfusion with DCiTreg, marked antiarthritic activity improved clinical scores and histological end-points were observed. The serological levels of inflammatory cytokines and anti-CII antibodies were low and TGF-βproduction was high in the DCiTreg-treated group. DCiTregalso induced new iTregsin vivo. Moreover, the inhibitory activity of DCiTregon CIA was lost following pretreatment with the inhibitor of indoleamine 2,3-dioxygenase (IDO). Collectively, these findings suggest that transferred iTregs could induce tolerogenic characteristics in splenic DCs and these cells could effectively dampen CIA in an IDO-dependent manner. Thus, the potential therapeutic effects of iTregs in CIA are likely maintained through the generation of tolerogenic DCsin vivo.

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Androgen receptor modulates Foxp3 expression in CD4+CD25+Foxp3+ regulatory T-cells

Molecular Biology of the Cell ◽

10.1091/mbc.e14-08-1323 ◽

2015 ◽

Vol 26 (15) ◽

pp. 2845-2857 ◽

Cited By ~ 51

Author(s):

Magdalena Walecki ◽

Florian Eisel ◽

Jörg Klug ◽

Nelli Baal ◽

Agnieszka Paradowska-Dogan ◽

...

Keyword(s):

T Cells ◽

Androgen Receptor ◽

Treg Cell ◽

Foxp3 Expression ◽

Treg Cells ◽

Strong Increase ◽

Histone H4 ◽

And Function

CD4+CD25+Foxp3+ regulatory T (Treg) cells are able to inhibit proliferation and cytokine production in effector T-cells and play a major role in immune responses and prevention of autoimmune disease. A master regulator of Treg cell development and function is the transcription factor Foxp3. Several cytokines, such as TGF-β and IL-2, are known to regulate Foxp3 expression as well as methylation of the Foxp3 locus. We demonstrated previously that testosterone treatment induces a strong increase in the Treg cell population both in vivo and in vitro. Therefore we sought to investigate the direct effect of androgens on expression and regulation of Foxp3. We show a significant androgen-dependent increase of Foxp3 expression in human T-cells from women in the ovulatory phase of the menstrual cycle but not from men and identify a functional androgen response element within the Foxp3 locus. Binding of androgen receptor leads to changes in the acetylation status of histone H4, whereas methylation of defined CpG regions in the Foxp3 gene is unaffected. Our results provide novel evidence for a modulatory role of androgens in the differentiation of Treg cells.

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Prostaglandin E2 directly inhibits the conversion of inducible regulatory T cells through EP2 and EP4 receptors via antagonizing TGF-β signalling

10.1101/2021.04.19.440391 ◽

2021 ◽

Author(s):

Marie Goepp ◽

Siobhan Crittenden ◽

You Zhou ◽

Adriano G Rossi ◽

Shuh Narumiya ◽

...

Keyword(s):

T Cells ◽

Cell Differentiation ◽

T Cell ◽

Prostaglandin E2 ◽

Th17 Cells ◽

Foxp3 Expression ◽

Treg Cells ◽

Itreg Cell

Background and Purpose: Regulatory T (Treg) cells are essential for control of inflammatory processes by suppressing Th1 and Th17 cells. The bioactive lipid mediator prostaglandin E2 (PGE2) promotes inflammatory Th1 and Th17 cells and exacerbates T cell-mediated autoimmune diseases. However, the actions of PGE2 on the development and function of Treg cells, particularly under inflammatory conditions, are debated. In this study, we examined whether PGE2 had a direct action on T cells to modulate de novo differentiation of Treg cells. Experimental Approach: We employed an in vitro T cell culture system of TGF-β-dependent Treg induction from naive T cells. PGE2 and selective agonists for its receptors, and other small molecular inhibitors were used. Mice with specific lack of EP4 receptors in T cells were used to assess Treg cell differentiation in vivo. Human peripheral blood T cells from healthy individuals were used to induce differentiation of inducible Treg cells. Key Results: TGF-β-induced Foxp3 expression and Treg cell differentiation in vitro was markedly inhibited by PGE2, which was due to interrupting TGF-β signalling. EP2 or EP4 agonism mimicked suppression of Foxp3 expression in WT T cells, but not in T cells deficient in EP2 or EP4, respectively. Moreover, deficiency of EP4 in T cells impaired iTreg cell differentiation in vivo. PGE2 also appeared to inhibit the conversion of human iTreg cells. Conclusion and Implications: Our results show a direct, negative regulation of iTreg cell differentiation by PGE2, highlighting the potential for selectively targeting the PGE2-EP2/EP4 pathway to control T cell-mediated inflammation.

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Vitamin A Impairs the Reprogramming of Tregs into IL-17-Producing Cells during Intestinal Inflammation

BioMed Research International ◽

10.1155/2015/137893 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 21

Author(s):

Gabriela Tejón ◽

Valeria Manríquez ◽

Jaime De Calisto ◽

Felipe Flores-Santibáñez ◽

Yessia Hidalgo ◽

...

Keyword(s):

T Cells ◽

Vitamin A ◽

Intestinal Inflammation ◽

Foxp3 Expression ◽

Treg Cells ◽

Transfer Model ◽

Effector Cells ◽

T Effector Cells

Maintaining the identity of Foxp3+regulatory T cells (Tregs) is critical for controlling immune responses in the gut, where an imbalance between Tregs and T effector cells has been linked to inflammatory bowel disease. Accumulating evidence suggests that Tregs can convert into Th17 cells and acquire an inflammatory phenotype. In this study, we used an adoptive transfer model of Ag-specific T cells to study the contribution of different factors to the reprogramming ofin vitro-generated Treg cells (iTreg) into IL-17-producing cells in a mouse model of gut inflammationin vivo. Our results show that intestinal inflammation induces the reprogramming of iTreg cells into IL-17-producing cells and that vitamin A restrains reprogramming in the gut. We also demonstrate that the presence of IL-2 during thein vitrogeneration of iTreg cells confers resistance to Th17 conversion but that IL-2 and retinoic acid (RA) cooperate to maintain Foxp3 expression following stimulation under Th17-polarizing conditions. Additionally, although IL-2 and RA differentially regulate the expression of different Treg cell suppressive markers, Treg cells generated under different polarizing conditions present similar suppressive capacity.

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Basiliximab impairs regulatory T cell (TREG) function and could affect the short-term graft acceptance in children with heart transplantation

Scientific Reports ◽

10.1038/s41598-020-80567-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jacobo López-Abente ◽

Marta Martínez-Bonet ◽

Esther Bernaldo-de-Quirós ◽

Manuela Camino ◽

Nuria Gil ◽

...

Keyword(s):

T Cells ◽

Heart Transplant ◽

Solid Organ Transplantation ◽

Foxp3 Expression ◽

Treg Cells ◽

Protective Role ◽

Regulatory Function ◽

Solid Organ

AbstractCD25, the alpha chain of the IL-2 receptor, is expressed on activated effector T cells that mediate immune graft damage. Induction immunosuppression is commonly used in solid organ transplantation and can include antibodies blocking CD25. However, regulatory T cells (Tregs) also rely on CD25 for their proliferation, survival, and regulatory function. Therefore, CD25-blockade may compromise Treg protective role against rejection. We analysed in vitro the effect of basiliximab (BXM) on the viability, phenotype, proliferation and cytokine production of Treg cells. We also evaluated in vivo the effect of BXM on Treg in thymectomized heart transplant children receiving BXM in comparison to patients not receiving induction therapy. Our results show that BXM reduces Treg counts and function in vitro by affecting their proliferation, Foxp3 expression, and IL-10 secretion capacity. In pediatric heart-transplant patients, we observed decreased Treg counts and a diminished Treg/Teff ratio in BXM-treated patients up to 6-month after treatment, recovering baseline values at the end of the 12-month follow up period. These results reveal that the use of BXM could produce detrimental effects on Tregs, and support the evidence suggesting that BXM induction could impair the protective role of Tregs in the period of highest incidence of acute graft rejection.

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THE SYNERGISTIC EFFECT OF LASER RADIATION AND IONIZING RADIATION ON MALIGNANT TUMORS IN VIVO AND IN VITRO

American Journal of Roentgenology ◽

10.2214/ajr.99.2.446 ◽

1967 ◽

Vol 99 (2) ◽

pp. 446-449 ◽

Cited By ~ 4

Author(s):

JAMES T. HELSPER ◽

GEORGE S. SHARP ◽

DONALD E. ROUNDS

Keyword(s):

Laser Radiation ◽

Ionizing Radiation ◽

Synergistic Effect ◽

Malignant Tumors

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Computational study for suppression of CD25/IL-2 interaction

Biological Chemistry ◽

10.1515/hsz-2020-0326 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Moein Dehbashi ◽

Zohreh Hojati ◽

Majid Motovali-bashi ◽

Mazdak Ganjalikhani-Hakemi ◽

Akihiro Shimosaka ◽

...

Keyword(s):

Small Molecules ◽

Cancer Progression ◽

Immune Escape ◽

De Novo ◽

Computational Study ◽

Treg Cells ◽

Homology Search ◽

Small Interfering Rnas

AbstractCancer recurrence presents a huge challenge in cancer patient management. Immune escape is a key mechanism of cancer progression and metastatic dissemination. CD25 is expressed in regulatory T (Treg) cells including tumor-infiltrating Treg cells (TI-Tregs). These cells specially activate and reinforce immune escape mechanism of cancers. The suppression of CD25/IL-2 interaction would be useful against Treg cells activation and ultimately immune escape of cancer. Here, software, web servers and databases were used, at which in silico designed small interfering RNAs (siRNAs), de novo designed peptides and virtual screened small molecules against CD25 were introduced for the prospect of eliminating cancer immune escape and obtaining successful treatment. We obtained siRNAs with low off-target effects. Further, small molecules based on the binding homology search in ligand and receptor similarity were introduced. Finally, the critical amino acids on CD25 were targeted by a de novo designed peptide with disulfide bond. Hence we introduced computational-based antagonists to lay a foundation for further in vitro and in vivo studies.

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T-cell–intrinsic Tif1α/Trim24 regulates IL-1R expression on TH2 cells and TH2 cell-mediated airway allergy

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1522287113 ◽

2016 ◽

Vol 113 (5) ◽

pp. E568-E576 ◽

Cited By ~ 10

Author(s):

Jimena Perez-Lloret ◽

Isobel S. Okoye ◽

Riccardo Guidi ◽

Yashaswini Kannan ◽

Stephanie M. Coomes ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Allergic Diseases ◽

Treg Cells ◽

Th2 Cells ◽

T Helper 2 ◽

Cytokines And Chemokines ◽

Th2 Cell

There is a paucity of new therapeutic targets to control allergic reactions and forestall the rising trend of allergic diseases. Although a variety of immune cells contribute to allergy, cytokine-secreting αβ+CD4+ T-helper 2 (TH2) cells orchestrate the type-2–driven immune response in a large proportion of atopic asthmatics. To identify previously unidentified putative targets in pathogenic TH2 cells, we performed in silico analyses of recently published transcriptional data from a wide variety of pathogenic TH cells [Okoye IS, et al. (2014) Proc Natl Acad Sci USA 111(30):E3081–E3090] and identified that transcription intermediary factor 1 regulator-alpha (Tif1α)/tripartite motif-containing 24 (Trim24) was predicted to be active in house dust mite (HDM)- and helminth-elicited Il4gfp+αβ+CD4+ TH2 cells but not in TH1, TH17, or Treg cells. Testing this prediction, we restricted Trim24 deficiency to T cells by using a mixed bone marrow chimera system and found that T-cell–intrinsic Trim24 is essential for HDM-mediated airway allergy and antihelminth immunity. Mechanistically, HDM-elicited Trim24−/− T cells have reduced expression of many TH2 cytokines and chemokines and were predicted to have compromised IL-1–regulated signaling. Following this prediction, we found that Trim24−/− T cells have reduced IL-1 receptor (IL-1R) expression, are refractory to IL-1β–mediated activation in vitro and in vivo, and fail to respond to IL-1β–exacerbated airway allergy. Collectively, these data identify a previously unappreciated Trim24-dependent requirement for IL-1R expression on TH2 cells and an important nonredundant role for T-cell–intrinsic Trim24 in TH2-mediated allergy and antihelminth immunity.

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Complementary Roles of GCN5 and PCAF in Foxp3+ T-Regulatory Cells

Cancers ◽

10.3390/cancers11040554 ◽

2019 ◽

Vol 11 (4) ◽

pp. 554 ◽

Cited By ~ 2

Author(s):

Yujie Liu ◽

Chunrong Bao ◽

Liqing Wang ◽

Rongxiang Han ◽

Ulf H. Beier ◽

...

Keyword(s):

Cell Biology ◽

T Regulatory Cells ◽

Treg Cells ◽

Epigenetic Therapy ◽

Lymphoid Tissues ◽

Allograft Survival ◽

Associated Factor ◽

General Importance

Functions of the GCN5-related N-acetyltransferase (GNAT) family of histone/protein acetyltransferases (HATs) in Foxp3+ T-regulatory (Treg) cells are unexplored, despite the general importance of these enzymes in cell biology. We now show that two prototypical GNAT family members, GCN5 (general control nonrepressed-protein 5, lysine acetyltransferase (KAT)2a) and p300/CBP-associated factor (p300/CBP-associated factor (PCAF), Kat2b) contribute to Treg functions through partially distinct and partially overlapping mechanisms. Deletion of Gcn5 or PCAF did not affect Treg development or suppressive function in vitro, but did affect inducible Treg (iTreg) development, and in vivo, abrogated Treg-dependent allograft survival. Contrasting effects were seen upon targeting of each HAT in all T cells; mice lacking GCN5 showed prolonged allograft survival, suggesting this HAT might be a target for epigenetic therapy in allograft recipients, whereas transplants in mice lacking PCAF underwent acute allograft rejection. PCAF deletion also enhanced anti-tumor immunity in immunocompetent mice. Dual deletion of GCN5 and PCAF led to decreased Treg stability and numbers in peripheral lymphoid tissues, and mice succumbed to severe autoimmunity by 3–4 weeks of life. These data indicate that HATs of the GNAT family have contributions to Treg function that cannot be replaced by the functions of previously characterized Treg HATs (CBP, p300, and Tip60), and may be useful targets in immuno-oncology.

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IL-17–producing invariant NKT cells in lymphoid organs are recent thymic emigrants identified by neuropilin-1 expression

Blood ◽

10.1182/blood-2011-01-329268 ◽

2011 ◽

Vol 118 (11) ◽

pp. 2993-3002 ◽

Cited By ~ 53

Author(s):

Pierre Milpied ◽

Bérangère Massot ◽

Amédée Renand ◽

Séverine Diem ◽

André Herbelin ◽

...

Keyword(s):

Cell Subset ◽

Treg Cells ◽

Lymphoid Organs ◽

Inkt Cell ◽

Inkt Cells ◽

Invariant Nkt Cells ◽

Neuropilin 1 ◽

Bona Fide

Abstract Despite increasing knowledge on the mechanisms of invariant natural killer T (iNKT)–cell development in the thymus, the function of recent thymic emigrant (RTE) iNKT cells remains largely unexplored, principally because of a lack of bona fide markers to distinguish RTE from long-lived iNKT cells. Whether the recently described IL-17–producing iNKT cell subset is part of RTE has notably not been addressed. In the present study, we show that neuropilin-1 (Nrp-1), a transmembrane receptor mainly found on T-regulatory (Treg) cells in the murine immune system, is specifically expressed on RTE iNKT cells in naive mice. We used the Nrp-1 marker to discriminate RTE from mature iNKT cells and compare their functions. We show that RTE iNKT cells proliferate more than mature iNKT cells after in vitro activation; that, unlike mature iNKT cells, most RTE iNKT cells fail to rapidly produce IFN-γ and IL-4 after in vivo activation; and, most importantly, that IL-17–producing iNKT cells in lymphoid organs of naive mice are contained within the RTE iNKT cell pool. Our results establish an accurate marker of RTE iNKT cells and reveal that continuous thymic output is required for pro-inflammatory IL-17 secretion, a key function of adult iNKT cells.

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