Carica papaya increases regulatory T cells and reduces IFN-γ+CD4+ T cells in healthy human subjects

Primary biliary cholangitis (PBC) is a chronic liver autoimmune disease with augmented T helper (Th) 1 and corresponding cytokine IFN-γ immune responses. Using 2-octynoic acid (2-OA) coupled to OVA (2-OA-OVA)-induced mouse models of autoimmune cholangitis (inducible chemical xenobiotic models of PBC), our previous study demonstrated that overexpression of IFN-γ in the model mice enhanced liver inflammation upon disease initiation, but subsequently led to the suppression of chronic inflammation with an increase in interleukin-30 (IL-30) levels. In this study, we investigated whether IL-30 had an immunosuppressive function and whether it could be part of an immune therapeutic regimen for PBC, by treating model mice with murine IL-30-expressing recombinant adeno-associated virus (AAV-mIL-30). We first defined the effects of AAV-mIL-30 in vivo by administering it to a well-known concanavalin A (ConA)-induced hepatitis model of mice and found that AAV-mIL-30 reduced the numbers of activated CD25+CD4+ T cells and the levels of serum IFN-γ and IL-12. In autoimmune cholangitis, decreased numbers of activated CD4+ T cells and Foxp3+ regulatory T cells were noted in the mice treated with AAV-mIL-30 at 3 weeks after the 2-OA-OVA immunization. Treatment with IL-30 did not change the features of autoimmune cholangitis including autoantibodies, cell infiltration, and collagen deposition in the liver at 11 weeks of examination. However, increased levels of cytokines and chemokines were observed. These results suggest that IL-30 suppresses not only CD4+ T cells but also regulatory T cells. Additionally, the administration of IL-30 did not suppress liver inflammation in the murine model of PBC.

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Reciprocal Interactions Between Conventional CD4 T Cells and Regulatory T Cells Alter the Properties of Regulatory T Cells and Promote the Development of IL-17 Producing Cells.

Blood ◽

10.1182/blood.v114.22.709.709 ◽

2009 ◽

Vol 114 (22) ◽

pp. 709-709

Author(s):

Lequn Li ◽

Jin Sub Kim ◽

Vassiliki A Boussiotis

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Cd4 T Cells ◽

Treg Cells ◽

Culture Conditions ◽

Th2 Cells ◽

Reciprocal Interactions ◽

Ifn Γ ◽

Th1 And Th2

Abstract Abstract 709 The differentiation and functional specialization of effector T cells allows for effective immune response to diverse insults. However, tight regulation of effector T cell responses is required for effective control of infections and avoidance of autoimmunity. Naïve CD4 T cells can differentiate into IFN-γ-secreting type I (Th1) cells and IL-4-secreting type II (Th2) cells. Recently, the Th1/Th2 paradigm of T helper (Th) cells differentiation has been expanded following the discovery of a third subset of effector Th cells that produce IL-17 (Th17). Regulatory T (Treg) cells have a remarkable ability to prevent naïve T cell differentiation into Th1 and Th2 cells and to suppress immune responses driven by Th1 and Th2 effector cells. The role of Treg cells in regulating IL-17 production remains undetermined. Some studies suggest that Treg cells may promote differentiation of naïve T cells into Th17 cells in the context of inflammatory cytokine milieu. The aim of our present study was to determine the role of Treg cells and conventional CD4+ T cells (Tconv) in the differentiation of IL-17 producing cells in the absence of exogenous cytokines and insults. Naïve Tconv cells stimulated with anti-CD3 mAb in the presence of antigen presenting cells (APCs) secreted significant amounts of IFN-γ and IL-4 but no detectable levels of IL-17, whereas Treg cells were incapable of producing any of these cytokines under the same culture conditions. Production of IFN-γ and IL-4 was significantly reduced by addition of Treg cells in the cultures of Tconv cells with anti-CD3 mAb and APC. In contrast, production of IL-17 was considerably enhanced in these co-culture conditions and the level of IL-17 displayed a positive correlation with the number of Treg cells added in the culture. To evaluate whether TCR-mediated stimulation of both Treg and Tconv cells was required for IL-17 production, we used Tconv cells and Treg cells from two different TCR transgenic mouse strains in H-2b background, 2D2 (MOG35-55-specific) and OT-II (OVA323-339-specific), respectively, and co-cultured them in the presence of APCs (H-2b). Production of IL-17 was not observed when either MOG peptide or OVA peptide alone was added in the cultures. In contrast, addition of both MOG and OVA resulted in production of IL-17, suggesting that simultaneous activation of Tconv and Treg cells was essential for induction of IL-17. To determine the source of IL-17 during co-culture of Treg and Tconv cells, we purified Treg cells from C57/B6 mice and co-cultured them with Tconv cells from the B6 congenic mouse strain B6.PL, which carry the Thy1a (Thy1.1) allele and can be easily recognized by flow cytomeric analysis using a Thy1.1-specific mAb. Detailed evaluation during co-culture revealed that a significant proportion of Thy1.1- T cells (the source of Treg) gradually downregulated expression of Foxp3 while obtaining expression of IL-17. In contrast, there was no significant change in the expression of either Foxp3 or IL-17 in the Thy1.1+ population (the source of Tconv), suggesting that Treg was the main source of IL-17 when stimulated in the presence of antigen and activated Tconv cells. Several cytokines have been implicated in the induction of IL-17, in particular, TGF-β. For this reason, we investigated the potential involvement of TGF-β in this conversion process. Addition of TGF-β to Tconv cultured with APCs and anti-CD3 mAb in the absence of Treg cells resulted in upregulation of Foxp3 but not IL-17. In contrast, addition of TGF-β neutralizing antibody to Tconv cultured with APC and anti-CD3 mAb in the presence of Treg, suppressed IL-17 production. Moreover, assessment of TGF-β signaling in Tconv and Treg cells revealed a dramatically increased level of Smad3 phosphorylation in Treg compared to Tconv cells, indicating a reduced threshold of TGF-β mediated signaling in Treg cells. Taken together, our data indicate that reciprocal interactions of Treg and Tconv cells are required for conversion of Treg into IL-17 producing cells and that TGF-β-mediated signaling is required for this process. In addition, our results provide evidence that Treg may convert into proinflammatory effectors producing IL-17, under conditions that promote Tconv differentiation into Treg cells. These observations provide a new dimension to our understanding of Treg cells functions and may have important implications in therapeutic strategies using Treg cells. Disclosures: No relevant conflicts of interest to declare.

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Inhaled endotoxin in healthy human subjects: A dose-related study on systemic effects and peripheral CD4+ and CD8+ T cells

Respiratory Medicine ◽

10.1016/j.rmed.2005.06.003 ◽

2006 ◽

Vol 100 (3) ◽

pp. 519-528 ◽

Cited By ~ 19

Author(s):

L.C. Loh ◽

B. Vyas ◽

V. Kanabar ◽

D.M. Kemeny ◽

B.J. O’Connor

Keyword(s):

T Cells ◽

Cd8 T Cells ◽

Human Subjects ◽

Systemic Effects ◽

Healthy Human ◽

Healthy Human Subjects

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Antigen-bearing immature dendritic cells induce peptide-specific CD8+ regulatory T cells in vivo in humans

Blood ◽

10.1182/blood.v100.1.174 ◽

2002 ◽

Vol 100 (1) ◽

pp. 174-177 ◽

Cited By ~ 262

Author(s):

Madhav V. Dhodapkar ◽

Ralph M. Steinman

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Regulatory T Cells ◽

Cd8 T Cells ◽

Cell Function ◽

Human Subjects ◽

Interferon Γ ◽

Healthy Human ◽

Immature Dendritic Cells

Abstract Regulatory T cells (TRs) can suppress the function of other effector T cells in the setting of autoimmunity, transplantation, and resistance to tumors. The mechanism for the induction of TRs has not been defined. We previously reported that an injection of immature dendritic cells (DCs) pulsed with influenza matrix peptide (MP) led 7 days later to antigen-specific silencing of effector T-cell function in the blood of 2 healthy human subjects. Here, we found that interferon-γ–producing effectors return by 6 months. Importantly, in mixing experiments, CD8+ T cells from the sample obtained 7 days after injection could suppress MP-specific effectors obtained before injection and those in recovery samples. This suppression or regulation was specific for the immunizing peptide (MP) and cell-dose dependent, and it required contact between the 2 samples. These data show the capacity of immature DCs to induce antigen-specific regulatory CD8+ T cells in humans.

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The 1800 MHz Radiofrequency Electromagnetic Fields Can Lead to a Reduction in the Number of CD4+T Cells, IL-2, IL-10, and IL-17a on PBMC Cultures

ACTA MEDICA IRANICA ◽

10.18502/acta.v58i9.4764 ◽

2020 ◽

Author(s):

Maimun Z Arthamin ◽

Anis Sulalah ◽

Resvina Resvina ◽

Chomsin Widodo ◽

,Agustina T Endharti ◽

...

Keyword(s):

T Cells ◽

Electromagnetic Fields ◽

Cd4 T Cells ◽

Mononuclear Cells ◽

Human Subjects ◽

T Helper ◽

T Helper 1 ◽

Healthy Human ◽

Peripheral Blood Mononuclear ◽

Radiofrequency Electromagnetic Fields

Although there have been many studies on the effects of electromagnetic fields on humans, scientists still have no agreement on the effects found because several studies showed no statistically significant effects. The effects of radiofrequency electromagnetic fields exposure on the immune system are varied, ranging from no effects to genotoxic effects on lymphocytes. Our study aimed to investigate whether exposure to 1800 MHz radiofrequency electromagnetic fields (RF-EMF) in variable durations and distances could lead to the dysregulation of T helper 1, 2, and 17. The peripheral blood mononuclear cells (PBMCs) cultures from healthy human subjects were exposed to 1800 MHz RF-EMF, with durations of 15, 30, 45, and 60 minutes and distances of 5 and 25 cm. We evaluated the effects of RF-EMF exposure on the number of CD4+ T cells, IL-2, IL-10, and IL-17a after 48 hours of culture with the flow cytometer. The closer the distance, the lower the number of CD4+ T cells. The longer the exposure, the lower the number of CD4+ T cells and the number of IL-2, IL-10, and IL-17a decreases significantly. CD4+ T cells expressing IL-2 increased significantly with the increase of the duration of 1800 MHz RF-EMF exposure (15, 30, and 45 min), but decreased at 60 minutes of exposure when compared to PBMCs without exposure. Sixty minutes of PBMC exposure to RF-EMF with a distance of 5 cm causes a significant reduction in the number of CD4+ T cells, the expression of IL-2, IL-10, and IL-17a.

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BMP4 Moderates Glycolysis and Regulates Activation and Interferon-Gamma Production in CD4+ T Cells

Frontiers in Immunology ◽

10.3389/fimmu.2021.702211 ◽

2021 ◽

Vol 12 ◽

Author(s):

Feng Huang ◽

Lei Hu ◽

Yuanmin Zhang ◽

Xingmin Qu ◽

Junji Xu

Keyword(s):

T Cells ◽

T Cell ◽

Growth Factor ◽

Regulatory T Cells ◽

Bone Regeneration ◽

Interferon Gamma ◽

Cd4 T Cells ◽

T Cell Development ◽

Ifn Γ

BMP4 is a key growth factor well known in promoting bone regeneration and has been reported to be able to regulate T cell development in the thymus. Here, we showed that BMP4 downregulates the activation of naïve CD4+ T cells and the IFN-γ production of CD4+ T cells without increasing regulatory T cells. BMP4 could also moderate glycolysis of T cells and regulate Hif1α expression. Furthermore, BMP4 showed a suppressive function on the IFN-γ production of CD4+ T cells in vivo. These findings indicating a mechanism by which BMP-4 may regulate activation and IFN-γ production in CD4+ T cells via metabolism moderation and suggests that BMP4 may be a potential therapeutic supplement in autoinflammatory diseases.

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A Selective and Potent Rock 2 Inhibitor (KD025) Decreases Human STAT3-Dependent IL-21 and IL-17 Production and Experimental Chronic Graft-Versus-Host Disease (cGVHD)

Blood ◽

10.1182/blood.v124.21.540.540 ◽

2014 ◽

Vol 124 (21) ◽

pp. 540-540 ◽

Cited By ~ 2

Author(s):

Alexandra Zanin-Zhorov ◽

Ryan Flynn ◽

Leo Luznik ◽

Angela Panoskaltsis-Mortari ◽

Du Jing ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

Oral Administration ◽

Ex Vivo ◽

Human Subjects ◽

Human Pbmcs ◽

Healthy Human ◽

Healthy Human Subjects ◽

Before And After

Abstract Pro-inflammatory IL-17-producing T cells termed Th17 are actively involved in the pathogenesis of GVHD. The development and function of Th17 cells is dependent on activation of STAT3, RORgt and IRF4 transcription factors. Aberrant activation of Rho-associated kinase 2 (ROCK2) leads to induction of IL-17 and IL-21 secretion via IRF4-dependent mechanism. KD025, is a potent and selective ROCK2 inhibitor, which when given to healthy human subjects down-regulated the ability of T cells to secrete IL-21 and IL-17, but not interferon (IFN)-g, in response to TCR stimulation in vitro (Figure 1). KD025 inhibits STAT3 phosphorylation which supports RORgt, Th17 generation, and IL-21 production. Concurrently, KD025 increases STAT5 phosphorylation and Treg suppressor function in a dose-responsive fashion. KD025 treatment therefore shifts Th17/Treg balance. Th17 cells have been linked to in vivo pro-inflammatory responses, antibody production, and fibrosis. Conversely, Tregs can offset these pathogenic responses. Given the profile of KD025, we tested the effects of this inhibitor on cGVHD pathogenesis in a multi-organ system rodent model of disease that is driven by IL-21 responses and is associated with lung, liver and intestinal fibrosis. We observed that Th17/Rorc deficient T cells are unable to mediate cGVHD pathogenesis. In mice with established cGVHD, therapy was initiated with 30, 100, or 150 mg/kg/dose of KD025 daily from d28-56. Treated mice had a dose dependent decrease in the development of pathogenic pulmonary function as determined by whole body plethysmography (Figure 2) which correlated with a marked reduction of antibody deposition in the lungs of treated mice to levels comparable to non-cGVHD controls. KD025 administration also resulted in a 2-fold decrease in collagen deposition in the lungs of mice treated with the highest dose of KD025. The spleens of mice treated with 150 mg/kg dose of KD025 had a decrease in the frequency of germinal centers compared to the vehicle treated mice. To determine the selective role of STAT3 on T cells, mice were transplanted with wildtype (WT) bone marrow (BM) and WT or inducible STAT3 deficient T cells. In parallel cohorts, the role of STAT3 in BM-derived B cells, precursors of germinal center B cells, was examined using WT vs inducible STAT3 deficient BM cells + WT T cells. We demonstrate here that mice transplanted with inducible STAT3 deficient T cells or BM cells had pulmonary function comparable to the healthy negative controls, suggesting that STAT3 is a potential therapeutic target in both T and B cells is necessary for the development of cGVHD and providing mechanistic insight into how KD025 may ameliorate active cGVHD. Studies are in progress to test KD025 administration in a murine scleroderma model using a minor histocompatibility antigen disparate donor-recipient strain that we have shown to be dependent upon STAT3 expressing donor T cells and a STAT3 inhibitor in both cGVHD models described here. Together, these data demonstrate that KD025 is effective at decreasing STAT3-dependent production of IL-21 and IL-17 and the use of KD025 is a potentially novel therapeutic intervention for the treatment of cGVHD. Fig 1 Oral administration of KD025 down-regulates the IL-17 and IL-21 secretion in human PBMCs upon stimulation ex vivo. Human PBMCs were purified from healthy human subjects before and after oral administration of KD025 at doses 40, 120, 240, 320 and stimulated ex vivo. Cytokine secretion was determined after 48 hours by ELISA. Fig 1. Oral administration of KD025 down-regulates the IL-17 and IL-21 secretion in human PBMCs upon stimulation ex vivo. Human PBMCs were purified from healthy human subjects before and after oral administration of KD025 at doses 40, 120, 240, 320 and stimulated ex vivo. Cytokine secretion was determined after 48 hours by ELISA. Fig 2 KD025 is an effective therapy for established murine cGVHD. Mice were given KD025 (150 mg/kg) d.28-56. PFTs indicate normal resistance, elastance and better compliance. Lung Ig deposition and fibrosis were comparable to BM controls. Fig 2. KD025 is an effective therapy for established murine cGVHD. Mice were given KD025 (150 mg/kg) d.28-56. PFTs indicate normal resistance, elastance and better compliance. Lung Ig deposition and fibrosis were comparable to BM controls. Disclosures No relevant conflicts of interest to declare.

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Proliferation and Activation Patterns of Naïve, Memory and Regulatory T Cells in Patients with Multiple Myeloma During Thalidomide, Interferon-α and Bortezomib Maintenance Therapy.

Blood ◽

10.1182/blood.v114.22.3880.3880 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3880-3880

Author(s):

Michael Hundemer ◽

Isabelle Herth ◽

Tobias Meissner ◽

Dirk Hose ◽

Anthony D Ho ◽

...

Keyword(s):

Multiple Myeloma ◽

T Cells ◽

Regulatory T Cells ◽

Maintenance Therapy ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Granzyme B ◽

Effector Memory ◽

Control Group ◽

Ifn Γ

Abstract Abstract 3880 Poster Board III-816 Hundemer and Herth (Contributed equally) Introduction In patients with Multiple myeloma, maintenance therapy after high-dose chemotherapy and autologous stem cell transplantation is performed with the aim to prolong remission duration and survival. Beside IFN-α, thalidomide and bortezomib are increasingly applied in maintenance protocols. In this prospective study we have analysed the implication of the various types of maintenance therapy on the patients T cell pattern and activation status. Patients and Methods T cells from 63 patients in clinical remission were analyzed. The median duration of remission was 38,6 months. Eighteen patients were treated with IFN-α, 22 with thalidomide, 7 with bortezomib and 16 patients received no maintenance therapy (control group). Peripheral blood mononuclear cells were isolated and stimulated with CD3/CD28 beads. Activated and nonactivated T cells were analyzed by flow cytometry (CD45RA, CD45RO, CCR7, CD28, CD200R, CD95, CD279, CD69, CD134 and TCRγ/δ) and ELISA (IFN-γ, perforine and granzym B). Furthermore the rate of IFN-γ-producing and regulatory T cells were analyzed by intracytoplasmatic staining and flow cytometry. Results All groups including the control group showed an up-regulation of CD69 and CD134 on CD4+ and CD8+ T cells after activation (p<0,001), on CD8+ T cells in the bortezomib-group only CD69 was upregulated (p=0,008). Patients treated with IFN-α showed a high rate of naïve T cells (CD45RA- and CCR7-positive), while in the thalidomide-group a high rate of effector memory T-cells (CD45RA- and CCR7-negative) were observed (CD45RA on CD8+ and CD4+ T cells: p<0,001, CCR7 on CD8+ T cells: p=0,03, CCR7 on CD4+ T cells: p=0,003). Regarding the surface marker CD28 on CD8+ T cells the IFN-α-group demonstrated a significant higher expression than the control-group (p=0,04) and the bortezomib-group a significant lower expression than the IFN-α- and the thalidomide-group (p=0,006 and p=0,02). Furthermore the rate of IFN-γ-producing CD4+ T cells was significant higher in the thalidomide-group than in the IFN-α-group after activation (p=0,02). On the basis of the cytoplasmatic staining of Foxp3 there was a trend to a higher amount of regulatory T cells in the thalidomide-group compared to the IFN-α-group (p=0,07). Analysis of IFN-y secretion by ELISA, an increases IFN-γ secretion could be demonstrated in all groups after activation (control group: p=0,002, IFN-α-group: p<0,001, thalidomide-group: p<0,001, bortezomib group: p=0,01), furthermore in all groups despite the bortezomib-group an increase of the granzyme B-production can be observed (control group: p=0,003, IFN-α-group: p=0,03, thalidomide-group: p<0,001). Regarding the activated state of the T cells the production of IFN-γ, perforine and granzyme B was significant higher in the thalidomide-group than in the IFN-α-group (IFN-γ: p=0,05, perforine: p=0,02, granzyme B: p=0,04). Furthermore the nonactivated and the activated T cells of the patients treated with thalidomide showed a significant higher production of granzyme B than the T cells of the control group (p=0,0003 and p=0,006). Conclusion During maintenance therapy, thalidomide promotes maturation and proliferation of effector memory T cells and regulatory T cells, while IFN-α treatment increases the number of naïve T cells and subsequently, the T cell activation in the thalidomide group was significantly higher than in the IFN-α group. These results have profound impact on the development of novel immunomodulating therapy strategies in the treatment of multiple myeloma. Disclosures: No relevant conflicts of interest to declare.

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In Vitro Generation of Interleukin 10–producing Regulatory CD4+ T Cells Is Induced by Immunosuppressive Drugs and Inhibited by T Helper Type 1 (Th1)– and Th2-inducing Cytokines

Journal of Experimental Medicine ◽

10.1084/jem.20011629 ◽

2002 ◽

Vol 195 (5) ◽

pp. 603-616 ◽

Cited By ~ 832

Author(s):

Franck J. Barrat ◽

Daniel J. Cua ◽

André Boonstra ◽

David F. Richards ◽

Chad Crain ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Cd4 T Cells ◽

Immunosuppressive Drugs ◽

T Helper ◽

Ifn Γ ◽

Th1 And Th2 ◽

Helper Type

We show that a combination of the immunosuppressive drugs, vitamin D3 and Dexamethasone, induced human and mouse naive CD4+ T cells to differentiate in vitro into regulatory T cells. In contrast to the previously described in vitro derived CD4+ T cells, these cells produced only interleukin (IL)-10, but no IL-5 and interferon (IFN)-γ, and furthermore retained strong proliferative capacity. The development of these IL-10–producing cells was enhanced by neutralization of the T helper type 1 (Th1)- and Th2–inducing cytokines IL-4, IL-12, and IFN-γ. These immunosuppressive drugs also induced the development of IL-10–producing T cells in the absence of antigen-presenting cells, with IL-10 acting as a positive autocrine factor for these T cells. Furthermore, nuclear factor (NF)-κB and activator protein (AP)-1 activities were inhibited in the IL-10–producing cells described here as well as key transcription factors involved in Th1 and Th2 subset differentiation. The regulatory function of these in vitro generated IL-10–producing T cells was demonstrated by their ability to prevent central nervous system inflammation, when targeted to the site of inflammation, and this function was shown to be IL-10 dependent. Generating homogeneous populations of IL-10–producing T cells in vitro will thus facilitate the use of regulatory T cells in immunotherapy.

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