scholarly journals Heterogeneity in FoxP3- and GARP/LAP-Expressing T Regulatory Cells in an HLA Class II Transgenic Murine Model of Necrotizing Soft Tissue Infections by Group A Streptococcus

2018 ◽  
Vol 86 (12) ◽  
Author(s):  
Suba Nookala ◽  
Santhosh Mukundan ◽  
Alexander Fife ◽  
Jeyashree Alagarsamy ◽  
Malak Kotb
Keyword(s):  
T Cells ◽  
T Regulatory Cells ◽  
Risk Allele ◽  
Inflammatory Responses ◽  
Group A Streptococcus ◽  
Soft Tissue Infections ◽  
Regulatory Cells ◽  
Necrotizing Soft Tissue Infections ◽  
Group A

ABSTRACT Invasive group A streptococcus (GAS) infections include necrotizing soft tissue infections (NSTI) and streptococcal toxic shock syndrome (STSS). We have previously shown that host HLA class II allelic variations determine the risk for necrotizing fasciitis (NF), a dominant subgroup of NSTI, and STSS by modulating responses to GAS superantigens (SAgs). SAgs are pivotal mediators of uncontrolled T-cell activation, triggering a proinflammatory cytokine storm in the host. FoxP3-expressing CD4+ CD25+ T regulatory cells (Tregs) comprise phenotypically and functionally heterogeneous subsets with a profound ability to suppress inflammatory responses. Specifically, activated Tregs, which express glycoprotein A repetitions predominant (GARP) and display latent transforming growth factor β1 (TGF-β1) complexes (latency-associated peptide [LAP]), exhibit strong immunosuppressive functions. The significance of Tregs that may participate in suppressing inflammatory responses during NSTI is unknown. Here, we phenotypically characterized FoxP3/GARP/LAP-expressing Tregs in GAS-infected or SAg (SmeZ)-stimulated splenocytes from transgenic (tg) mice expressing human HLA-II DRB1*15 (DR15 allele associated with nonsevere NF/STSS-protective responses) or DRB1*0402/DQB1*0302 (DR4/DQ8 alleles associated with neutral risk for combined NF/STSS). We demonstrated both in vivo and in vitro that the neutral-risk allele upregulates expression of CD4+ CD25+ activated effector T cells, with a significantly lower frequency of Foxp3+/GARP+ LAP− but higher frequency of Foxp3− LAP+ Tregs than seen with the protective allele. Additional in vitro studies revealed that the presentation of SmeZ by the neutral-risk allele significantly increases proliferation and expression of effector cytokines gamma interferon (IFN-γ) and interleukin-2 (IL-2) and upregulates CD4+ CD25+ T cell receptors (TCRs) carrying specific Vβ 11 chain (TCRVβ11+) T cells and Th1 transcription factor Tbx21 mRNA levels. Our data suggest that neutral-risk alleles may drive Th1 differentiation while attenuating the induction of Tregs associated with suppressive function.

scholarly journals BDC12-4.1 T-Cell Receptor Transgenic Insulin-Specific CD4 T Cells Are Resistant to In Vitro Differentiation into Functional Foxp3+ T Regulatory Cells

PLoS ONE ◽  
2014 ◽  
Vol 9 (11) ◽  
pp. e112242 ◽  
Author(s):  
Ghanashyam Sarikonda ◽  
Georgia Fousteri ◽  
Sowbarnika Sachithanantham ◽  
Jacqueline F. Miller ◽  
Amy Dave ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cd4 T Cells ◽  
T Regulatory Cells ◽  
Cell Receptor ◽  
Regulatory Cells ◽  
In Vitro Differentiation

scholarly journals Phosphoantigen-activated Vγ2Vδ2 T cells antagonize IL-2–induced CD4+CD25+Foxp3+ T regulatory cells in mycobacterial infection

Blood ◽  
2009 ◽  
Vol 113 (4) ◽  
pp. 837-845 ◽  
Author(s):  
Guangming Gong ◽  
Lingyun Shao ◽  
Yunqi Wang ◽  
Crystal Y. Chen ◽  
Dan Huang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Treatment Regimen ◽  
T Regulatory Cells ◽  
Mycobacterial Infection ◽  
T Cell Subsets ◽  
Regulatory Cells ◽  
Ifn Γ ◽  
Vγ2vδ2 T Cells

Abstract Although Foxp3+ T regulatory cells (Tregs) are well documented for their ability to suppress various immune cells, T-cell subsets capable of counteracting Tregs have not been demonstrated. Here, we assessed phosphoantigen-activated Vγ2Vδ2 T cells for the ability to interplay with Tregs in the context of mycobacterial infection. A short-term IL-2 treatment regimen induced marked expansion of CD4+CD25+Foxp3+ T cells and subsequent suppression of mycobacterium-driven increases in numbers of Vγ2Vδ2 T cells. Surprisingly, activation of Vγ2Vδ2 T cells by adding phosphoantigen Picostim to the IL-2 treatment regimen down-regulated IL-2–induced expansion of CD4+CD25+Foxp3+ T cells. Consistently, in vitro activation of Vγ2Vδ2 T cells by phosphoantigen plus IL-2 down-regulated IL-2–induced expansion of CD4+CD25+Foxp3+ T cells. Interestingly, anti–IFN-γ–neutralizing antibody, not anti–TGF-β or anti–IL-4, reduced the ability of activated Vγ2Vδ2 T cells to down-regulate Tregs, suggesting that autocrine IFN-γ and its network contributed to Vγ2Vδ2 T cells' antagonizing effects. Furthermore, activation of Vγ2Vδ2 T cells by Picostim plus IL-2 treatment appeared to reverse Treg-driven suppression of immune responses of phosphoantigen-specific IFNγ+ or perforin+ Vγ2Vδ2 T cells and PPD-specific IFNγ+αβ T cells. Thus, phos-phoantigen activation of Vγ2Vδ2 T cells antagonizes IL-2–induced expansion of Tregs and subsequent suppression of Ag-specific antimicrobial T-cell responses in mycobacterial infection.

Adenosine A2A Receptor Agonist Mediated Prevention of Graft-Versus Host Disease In the Mouse Is Associated with An Increase of T-Regulatory Cells In Target Organs.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3744-3744
Author(s):  
Kyu Lee Han ◽  
Sherry Walker ◽  
Harry L. Malech ◽  
Elizabeth M. Kang
Keyword(s):  
T Cells ◽  
Mouse Model ◽  
Acute Gvhd ◽  
T Regulatory Cells ◽  
Treated Group ◽  
Regulatory Cells ◽  
High Power Field ◽  
Target Organs ◽  
A2ar Agonist

Abstract Abstract 3744 Graft versus host disease (GVHD) is a serious complication of allogenic hematopoietic stem cell transplantation (HSCT) affecting primarily the liver, intestine, skin and lymphoid organs. T-regulatory cells (Tregs) are a subset of T cells that are characterized by CD4+CD25high and express the Foxp3 transcription factor. There is increasing recognition that Tregs likely are important in preventing development, reducing the severity and/or mediating resolution of GVHD. It has been reported that giving donor Tregs will suppress development of GVHD in a mouse model; however it is not clear whether the immunologic suppression by Tregs occurs in the target organs. Agonists of the Gs-coupled Adenosine A2A receptor (A2AR) agonists have been demonstrated to terminate inflammation and improve survival in solid organ transplant ischemia models. We previously have reported that the A2AR specific agonist, ATL146e, also can decrease the incidence and severity of GVHD as well as improve survival of mice in a GVHD transplant mouse model. In this same GVHD mouse model, ATL146e treatment increases the number of donor derived CD4+CD25highFoxp3+ Tregs. In order to further understand the role of the agonist in GVHD abrogation we performed studies looking at A2AR agonist mediated appearance of Tregs in the target organs affected by GVHD in this model. Using a parental into irradiated F1 offspring transplant model (C57BL/6J [B6, H-2b] -> B6D2F1/J [BDF1, H-2b/d]) we can induce GVHD as manifested by weight loss and mortality in 100% of mice by infusing an additional 10 million donor T cells into mice previously engrafted with 10 million bone marrow donor cells using 850cGy conditioning. We administered the A2AR specific agonists, ATL1223 or ATL370, or a PBS control by osmotic mini pumps resulting in continuous subcutaneous infusion for 14 days starting one day before the donor T cell infusion. Mice that received only the donor bone marrow transplant and not the additional donor T cells did not develop GVHD and served as an additional control. We collected ear and colon biopsies from the transplanted mice to assess these target organs (skin and gut) usually affected by GVHD in this model. Tissue was obtained, placed in 10% formalin and paraffin embedded and stained by immunohistochemistry (IHC) for intracellular FoxP3 by incubating overnight with 1:200 mouse anti-mouse/human/rat—FoxP3 IgG. The slides were washed and then incubated with anti-mouse IgG conjugated to Tetramethylrhodamine (TRITC). We then counted the number of Foxp3+ cells per high power field. We also examined whether specific agonist activation of A2AR can increase the number of Tregs in vitro by culturing CD4+ CD25− cells in the presence of either TGF-beta and/or the A2AR specific agonists. As in our previous studies with the specific A2AR agonist ATL146e, the agonists ATL1223 and ATL370 also were effective at preventing the acute GVHD syndrome of weight loss and mortality seen in the PBS treated controls. Treatment with these agonists resulted in an increase in CD4+CD25+FoxP3+ Tregs in the spleen compared to the PBS treated group at days 14 to 20 after HSCT. In addition we were able to document significant increases in the number of Foxp3 positive T lymphocytes infiltrating skin and colon compared to the PBS treated group. The number of Foxp3+ T cells per high power field was 14 ± 6 in the control and 64 ± 14 in the A2AR agonist treated mice (p = 0.0281). Finally from our in vitro data we also observed a 4.2 to 5.4 fold increase in the number of Foxp3+ Tregs in vitro after A2AR activation compared to TGF beta treatment only. Thus we have confirmed that the specific activation of A2AR inhibits acute GVHD through the increase of donor-derived CD4+ CD25+ FoxP3+ immunosuppressive T regulatory cells in vivo and in vitro. Furthermore, our histological observation suggests the possibility that increased Tregs by treatment with A2AR specific agonist is responsible for suppressing the immune response in GVHD target tissues. Therefore, our observation provides additional mechanistic basis for the anti-inflammatory capacity of A2AR agonist in acute GVHD. Additional studies are ongoing to further elucidate the mechanism by which A2AR specific agonist increases Tregs. Disclosures: No relevant conflicts of interest to declare.

Ibrutinib Treatment Reduces Both T-Regulatory Cells and B-Regulatory Cell Phenotype in Malignant B Cells in Chronic Lymphocytic Leukemia Patients

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2940-2940 ◽  
Author(s):  
Meixiao Long ◽  
Kyle A. Beckwith ◽  
Kami J. Maddocks ◽  
Carolyn Cheney ◽  
Jennifer A. Woyach ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Research Funding ◽  
T Regulatory Cells ◽  
Surface Expression ◽  
Lymphocytic Leukemia ◽  
Regulatory Cells ◽  
Reduced Frequency ◽  
Fold Reduction

Abstract Introduction: Chronic lymphocytic leukemia (CLL) has multiple mechanisms of active immune suppression including expansion of T-regulatory cells which increases with progression of the disease. In addition, the malignant CLL cells were found to produce IL-10 in vitro and functionally recapitulate the phenotype of regulatory B cells. These regulatory "B10" (capable of producing IL10 after hours in vitro stimulation) or "B10 pro" (capable of producing IL10 after 2 days in vitro conditioning) are generally rare in healthy individuals, and play an important role in regulating inflammatory and autoimmune process. Similarly, CLL cells can exert tumor specific as well as global immune suppressive effect via IL-10 production. Ibrutinib, the first in class irreversible BTK inhibitor has been proved to be a safe and effective therapy for CLL. Recently we and others have demonstrated favorable cellular immune modulatory effects of ibrutinib through inhibition of an alternative target interleukin-2 induced T-cell kinase (ITK) that promotes Th1 CD4 polarization. Herein, we explore influence of ibrutinib on other immune suppressive features including T-regulatory cells and the B-regulatory phenotype associated with CLL cells. Methods: PBMCs were collected from nine previously treated CLL patients treated with 420mg of ibrutinib daily per clinical trial OSU-11133 (NCT01589302) at the time of pretreatment, cycle 3 day 1 and cycle 6 day 1. For Brief stimulation (B10 condition), cryopreserved PBMCs were thawed and stimulated with PMA/Ionomycin/Golgi-stop plus CpG for 5 hours. For prolonged stimulation (B10-Pro condition), PBMCs were stimulated with CpG plus CD40L for 48 hours, PMA / Ionomycin / Golgi-stop were added for final 5 hours. The cells were then fixed / permeabilized and stained for intracellular IL-10. For FOXP3 staining, PBMCs were permeabilized and fixed with Foxp3 Buffer Set from eBioscience, and were stained with stained with PE conjugated anti-human Foxp3 antibody (clone 259D/C7). Results: Significant IL-10 production was detected in 8 out 9 patient's CLL cells after 48 hours in vitro stimulation. Interestingly, CLL cells collected from patients treated with ibrutinib in vivo were significantly impaired in their capacity to make IL-10 in 7 out of the 8 patients whose CLL cells were capable of producing IL-10. On average, there is more than 4 fold reduction( P< 0.01) in the frequency of cells producing IL-10 by cycle 3, more than 5 fold reduction (P< 0.01) by cycle 6. (Figure 1 A, upper panel). IL-10 production after a brief 5 hour in vitro stimulation was observed in 4 out of the 9 patients studied, though the frequencies of IL-10 producing cells were low (Figure 1 A, lower panel). Samples collected post-ibrutinib treatment showed a trend towards reduced frequency of IL-10 producing CLL cells after 5 hour stimulation. We have also shown that during the first two cycles of ibrutinib, patients' plasma levels of IL-10 decreased. Analysis of potential immunosuppressive molecules revealed a dramatic reduction in surface expression of CD200, BTLA and PD-1 in CLL cells collected post ibrutinib treatment compared to pre-treatment samples (Figure 1B). We also found that for all the patients analyzed, the percentage of CD4+/Foxp3+ and CD4+/CD25+/Foxp3+ regulatory T cells were significantly reduced in samples collected after ibrutinib treatment. The difference is more dramatic for CD25+Foxp3+ cells (figure 1C). Conclusion: Here we demonstrate a significant decrease in the frequency of T-regulatory cells and IL-10 competent "B-reg" like leukemia cells in CLL patients after ibrutinib treatment. Ability of CLL cells to produce IL-10 and their regulatory B cell like features are considered to play a major role in mediating both global and tumor specific immunosuppression in CLL patients. Ibrutinib has been reported to enhance the immune response against B cell lymphoma in a mouse model. Our findings provide potential mechanisms by which ibrutinib treatment relieve the immunosuppressive effect of malignant B cells, thus enhancing global as well as tumor specific immunity. The main mechanisms likely include impaired IL-10 production capability and reduced surface expression of immunosuppressive molecules by CLL cells, as well as reduced frequency of regulatory T cells and IL-10 producing T cells. Figure 1. Figure 1. Figure 2. Figure 2. Figure 3. Figure 3. Disclosures Maddocks: Novartis: Research Funding; Janssen: Research Funding; Pharmacyclics: Consultancy, Research Funding. Byrd:Acerta Pharma BV: Research Funding; Acerta Pharma BV: Research Funding.

scholarly journals Correlation Between Immunoglobulin Dose Administered and Plasma Neutralization of Streptococcal Superantigens in Patients With Necrotizing Soft Tissue Infections

2020 ◽  
Vol 71 (7) ◽  
pp. 1772-1775 ◽  
Author(s):  
Helena Bergsten ◽  
Martin Bruun Madsen ◽  
Francois Bergey ◽  
Ole Hyldegaard ◽  
Steinar Skrede ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Clinical Trials ◽  
T Cell ◽  
Soft Tissue ◽  
Negative Correlation ◽  
Group A Streptococcus ◽  
T Cell Proliferation ◽  
Soft Tissue Infections ◽  
Necrotizing Soft Tissue Infections ◽  
Group A

Abstract Analyses of plasma collected pre- and postadministration of intravenous immunoglobulin (IVIG) from patients with group A Streptococcus necrotizing soft tissue infections demonstrated a negative correlation between IVIG dose and toxin-triggered T-cell proliferation (r = −.67, P &lt; .0001). One 25-g IVIG dose was sufficient to yield plasma-neutralizing activity against streptococcal superantigens. Clinical Trials Registration. NCT 01790698 and NCT02111161.

scholarly journals Unregulated antigen-presenting cell activation by T cells breaks self tolerance

2018 ◽  
Vol 116 (3) ◽  
pp. 1007-1016 ◽  
Author(s):  
Jaeu Yi ◽  
Jisun Jung ◽  
Sung-Wook Hong ◽  
Jun Young Lee ◽  
Daehee Han ◽  
...  
Keyword(s):  
T Cells ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
T Regulatory Cells ◽  
Small Subset ◽  
Regulatory Cells ◽  
High Affinity ◽  
Self Tolerance ◽  
Antigen Presenting

T cells proliferate vigorously following acute depletion of CD4+ Foxp3+ T regulatory cells [natural Tregs (nTregs)] and also when naive T cells are transferred to syngeneic, nTreg-deficient Rag1−/− hosts. Here, using mice raised in an antigen-free (AF) environment, we show that proliferation in these two situations is directed to self ligands rather than food or commensal antigens. In both situations, the absence of nTregs elevates B7 expression on host dendritic cells (DCs) and enables a small subset of naive CD4 T cells with high self affinity to respond overtly to host DCs: bidirectional T/DC interaction ensues, leading to progressive DC activation and reciprocal strong proliferation of T cells accompanied by peripheral Treg (pTreg) formation. Likewise, high-affinity CD4 T cells proliferate vigorously and form pTregs when cultured with autologous DCs in vitro in the absence of nTregs: this anti-self response is MHCII/peptide dependent and elicited by the raised level of B7 on cultured DCs. The data support a model in which self tolerance is imposed via modulation of CD28 signaling and explains the pathological effects of superagonistic CD28 antibodies.

scholarly journals Human in vitro induced T regulatory cells and memory T cells share common demethylation of specific FOXP3 promoter region

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Philippe Bégin ◽  
Janika Schulze ◽  
Udo Baron ◽  
Sven Olek ◽  
Rebecca N. Bauer ◽  
...  
Keyword(s):  
T Cells ◽  
Promoter Region ◽  
T Regulatory Cells ◽  
Memory T Cells ◽  
Regulatory Cells

Leukemic Transformation Induces the Constitutive Expression of Indoleamine 2,3-Dyoxigenase Which Directly Increases CD4+CD25+ T Regulatory Cells.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1210-1210
Author(s):  
Antonio Curti ◽  
Simona Pandolfi ◽  
Michela Aluigi ◽  
Barbara Valzasina ◽  
Alessandro Isidori ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
T Regulatory Cells ◽  
Active Form ◽  
Constitutive Expression ◽  
T Cell Proliferation ◽  
Regulatory Cells ◽  
Foxp3 Mrna

Abstract The expression of the catalytic enzyme of tryptophan, indoleamine 2,3-dyoxigenase (IDO) in different cellular subsets, including solid tumors, has been recently identified as a T-cell inhibitory effector pathway. Here, we show that unlikely normal hematopoietic CD34+ cells expressing IDO only upon stimulation with IFN-γ, acute myeloid leukemia (AML) cells constitutively express IDO and inhibit allogeneic T-cell proliferation. IDO expression correlates with increased CD4+CD25+Foxp3+ T cells in AML patients at diagnosis. In vitro, IDO+ AML cells increase the percentage and the absolute number of CD4+CD25bright T cells, also expressing surface CTLA-4 and Foxp3 mRNA. The addition of the IDO-inhibitor, 1-methyl tryptophan (1-MT), completely abrogates such increase. Purified CD4+CD25+ T cells obtained from coculture with IDO+ AML cells are not proliferating and unable to produce IL-2. They also inhibit naive T-cell proliferation and Th1 skewing. Co-culture with IDO+ AML cells results in the conversion of CD4+CD25− into CD4+CD25+ T cells and the addition of 1-MT completely abrogates this effect. In mice, intrasplenic injection of IDO-expressing leukemia/lymphoma A20 cells induces the increase of CD4+CD25+ T cells, which can be blocked by 1-MT treatment. These data suggest that AML cells have the capacity to directly increase a population of T regulatory cells through the constitutive expression of the functionally active form of IDO. IDO expression can be regarded as a novel mechanism of leukemia escape from immune control and its inhibition may represent a novel anti-leukemia therapeutic strategy.

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