scholarly journals The TLR9 Agonist Cobitolimod Induces IL10-Producing Wound Healing Macrophages and Regulatory T Cells in Ulcerative Colitis

2019 ◽  
Vol 14 (4) ◽  
pp. 508-524 ◽  
Author(s):  
Heike Schmitt ◽  
Julia Ulmschneider ◽  
Ulrike Billmeier ◽  
Michael Vieth ◽  
Patrizio Scarozza ◽  
...  

Abstract Background and Aims The topically applied Toll-like receptor 9 [TLR9] agonist cobitolimod is a first-in-class DNA-based oligonucleotide with demonstrated therapeutic efficacy in clinical trials with ulcerative colitis [UC] patients. We here characterized its anti-inflammatory mechanism in UC. Methods Luminal cobitolimod administration was evaluated in an experimental dextran sodium sulfate [DSS]-induced colitis model. Cultured blood and mucosal cells from UC patients were treated with cobitolimod and analysed via microarray, quantitative real-time PCR, ELISA and flow cytometry. Intestinal slides of cobitolimod-treated UC patients were analysed by immunohistochemistry. Results Cobitolimod administration markedly suppressed experimental colitis activity, and microarray analyses demonstrated mucosal IL10 upregulation and suppression of IL17 signalling pathways. Cobitolimod treatment was associated with significant induction of mucosal IL10+Tr1 and Treg cells and suppression of Th17 cells. TLR9 knockout mice indicated that cobitolimod requires TLR9 signalling for IL10 induction. In UC patients, mucosal TLR9 levels correlated with severity of inflammation. Cobitolimod inhibited IL17A and IL17F, but increased IL10 and FoxP3 expression in cultured intestinal UC T cells. Cobitolimod-mediated suppression of intestinal IL17+T cells was abrogated by IL10 blockade. Furthermore, cobitolimod led to heightened IL10 production by wound healing macrophages. Immunohistochemistry in intestinal biopsies of cobitolimod-treated UC patients indicated increased presence of IL10+mononuclear and regulatory T cells, as well as reduction of IL17+cells. Conclusion Activation of TLR9 via cobitolimod might represent a novel therapeutic approach in UC, as it suppresses Th17 cells and induces anti-inflammatory IL10+macrophages and regulatory T cells, thereby modifying the dysregulated intestinal cytokine balance. Podcast This article has an associated podcast which can be accessed at https://academic.oup.com/ecco-jcc/pages/podcast

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mei Ding ◽  
Rajneesh Malhotra ◽  
Tomas Ottosson ◽  
Magnus Lundqvist ◽  
Aman Mebrahtu ◽  
...  

AbstractRegulatory T cells (Tregs) are the key cells regulating peripheral autoreactive T lymphocytes. Tregs exert their function by suppressing effector T cells. Tregs have been shown to play essential roles in the control of a variety of physiological and pathological immune responses. However, Tregs are unstable and can lose the expression of FOXP3 and suppressive functions as a consequence of outer stimuli. Available literature suggests that secreted proteins regulate Treg functional states, such as differentiation, proliferation and suppressive function. Identification of secreted proteins that affect Treg cell function are highly interesting for both therapeutic and diagnostic purposes in either hyperactive or immunosuppressed populations. Here, we report a phenotypic screening of a human secretome library in human Treg cells utilising a high throughput flow cytometry technology. Screening a library of 575 secreted proteins allowed us to identify proteins stabilising or destabilising the Treg phenotype as suggested by changes in expression of Treg marker proteins FOXP3 and/or CTLA4. Four proteins including GDF-7, IL-10, PAP and IFNα-7 were identified as positive regulators that increased FOXP3 and/or CTLA4 expression. PAP is a phosphatase. A catalytic-dead version of the protein did not induce an increase in FOXP3 expression. Ten interferon proteins were identified as negative regulators that reduced the expression of both CTLA4 and FOXP3, without affecting cell viability. A transcriptomics analysis supported the differential effect on Tregs of IFNα-7 versus other IFNα proteins, indicating differences in JAK/STAT signaling. A conformational model experiment confirmed a tenfold reduction in IFNAR-mediated ISG transcription for IFNα-7 compared to IFNα-10. This further strengthened the theory of a shift in downstream messaging upon external stimulation. As a summary, we have identified four positive regulators of FOXP3 and/or CTLA4 expression. Further exploration of these Treg modulators and their method of action has the potential to aid the discovery of novel therapies for both autoimmune and infectious diseases as well as for cancer.


2021 ◽  
Vol 22 (21) ◽  
pp. 11977
Author(s):  
Jocelyn C. Pérez-Lara ◽  
Enrique Espinosa ◽  
Leopoldo Santos-Argumedo ◽  
Héctor Romero-Ramírez ◽  
Gabriela López-Herrera ◽  
...  

CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38+CD25+ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38+ regulatory T-cells are more suppressive than CD38− regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Faslpr/J). Additionally, B6.MRL-Faslpr/J mice showed a decreased proportion of CD38+ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells.


Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Dan Ye ◽  
Yun Xu

Both resident microglia and infiltrated peripheral T cells have been proved to play important roles in the pathology of stroke. It is well accepted that activated microglia exert dual roles, including pro-inflammatory (M1) and anti-inflammatory (M2) functions. However, the mechanism regulating microglial polarization remains elusive. T cells are recruited into the ischemic area within 24 h after stroke, which also exhibit pro-inflammatory (Th1, Th17) and anti-inflammatory (Th2, Treg) functions. The interaction between microglia and T cells after stroke is barely understood, which may be served as modifiers of pathobiology in stroke. Here we described the role of T cells in the microglial polarization in mouse experimental stroke. We isolated T cells from spleens of MCAO mice at 24 h and 72 h, respectively, and then added to cultured microglia for 24 h. Our results indicated that splenic T cells obtained at 24 h after MCAO selectively promoted microglia polarize to a pro-inflammatory (M1) state, while T cells obtained at 72 h, favored microglia polarize to an anti-inflammatory (M2) state. The results of flow cytometry showed that Th1 and Th17 cells increased at 24 h after MCAO while Th2 and Treg cells increased at 72 h after MCAO. This study implicates that distinct subtypes of T cells contribute differentially to microglial polarization after stroke onset. Therefore, treatments aiming at modulating the ratios of T cells to anti-inflammatory cells have the potential to induce microglial polarize to M2 phenotype and improve the outcome of ischemic stroke.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1347-1347
Author(s):  
Zhi-Zhang Yang ◽  
Anne J. Novak ◽  
Thomas E. Witzig ◽  
Stephen M. Ansell

Abstract Numerous clinical therapies have attempted to modulate tumor cell immunity, but for the most part, have proven unsuccessful. The inability to produce or augment an effective immune response is due in part to regulatory T (Treg) cells, which inhibit CD4 and CD8 T cell function. Our group has recently shown that Treg cell numbers are elevated in NHL tumors and that NHL B cells induce the development of Treg cells thereby inhibiting anti-tumor responses. The ability of NHL B cells to direct the cellular composition of their microenvironment is critical to our understanding of tumor immunity and we therefore wanted to determine if NHL B cells also directed the expansion or reduction of other T cell populations. IL-17-secreting CD4+ T cells (TH17), a newly characterized CD4+ T helper cell lineage, promote inflammation and play an important role in autoimmune disease. IL-17 has been shown to inhibit tumor cell growth suggesting a potential role for TH17 cells in anti-tumor immunity. We therefore set out to determine if TH17 cells were present in NHL tumors and whether or not their numbers were regulated by NHL B cells. Using unsorted mononuclear cells from malignant lymph nodes, we were unable to detect IL-17 expression in resting CD4+ T cells or CD4+ T cells activated with PMA/Ionomycin stimulation (less than 1%). However, IL-17-secreting CD4+ T cells could be detected in significant numbers in inflammatory tonsil and normal PBMCs. Interestingly, depletion of CD19+ NHL B cells from mononuclear cells obtained from patient biopsies resulted in detection of a clear population of IL-17-secreting CD4+ T cells (5%). These results suggest that NHL B cells suppress TH17 cell differentiation. The frequency of IL-17-secreting CD4+ T cells could not be further enhanced by the addition of exogenous TGF-b and IL-6, a cytokine combination favoring for TH17 differentiation, suggesting a further impairment of TH17 cell differentiation in the tumor microenvironment. In contrast, Foxp3 expression could be detected in resting CD4+ T cells (30%) and could be induced in CD4+CD25−Foxp3− T cells activated with TCR stimulation (28%). Contrary to the inhibition of TGF-b-mediated TH17 differentiation, Foxp3 expression could be dramatically upregulated by TGF-b in intratumoral CD4+ T cells (35%). In addition, lymphoma B cells strongly enhanced Foxp3 expression in intratumoral CD4+CD25−Foxp3−. Furthermore, when added together, the frequency of Foxp3+ T cells and Foxp3-inducible cells reached up to 60% of CD4+ T cells in tumor microenvironment of B-cell NHL. These findings suggest that the balance of effector TH17 cells and inhibitory Treg cells is disrupted in B-cell NHL and significantly favors the development of inhibitory Treg cells. Our data indicate that lymphoma B cells are key factor in regulating differentiation of intratumoral CD4+ T cells toward inhibitory CD4+ T cells.


2021 ◽  
Author(s):  
Marie Goepp ◽  
Siobhan Crittenden ◽  
You Zhou ◽  
Adriano G Rossi ◽  
Shuh Narumiya ◽  
...  

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.


2021 ◽  
Author(s):  
Mark Mensink ◽  
Ellen Schrama ◽  
Maartje van den Biggelaar ◽  
Derk Amsen ◽  
Jannie Borst ◽  
...  

The CD4+ regulatory T (Treg) cell lineage, as defined by FOXP3 expression, comprises thymus-derived (t)Treg cells and peripherally induced (p)Treg cells. In human, naive tTreg cells can be purified from blood, but occur in low abundance, while effector pTreg and tTreg cell populations cannot be purified for lack of discriminating cell surface markers. Therefore, studies often employ TGF-β-induced (i)Treg cells that are generated from CD4+ conventional T (Tconv) cells in vitro. Here, we describe the relationship of iTreg cells to tTreg and Tconv cells, as optimally purified from human blood. Global proteomic analysis revealed that iTreg, tTreg and Tconv cell populations each have a unique protein expression pattern. We next used as a benchmark a previously defined proteomic signature that discerns ex vivo naive and effector phenotype Treg cells from Tconv cells and reflects unique Treg cell properties. This Treg cell core signature was largely absent from iTreg cells, while clearly present in simultaneously analyzed tTreg cells. In addition, we used a proteomic signature that distinguishes ex vivo effector Treg cells from Tconv cells and naive Treg cells. This effector Treg cell signature was partially present in iTreg cells. Thus, iTreg cells are distinct from tTreg cells and largely lack the common Treg cell proteomic signature. However, they do have certain protein expression features in common with ex vivo effector Treg cells. These data demonstrate the utility of the core and effector Treg cell signatures as tools to define Treg cell populations and encourage the use of ex vivo Treg cells for functional analyses.


2021 ◽  
Vol 11 ◽  
Author(s):  
Terhi Ruohtula ◽  
Anita Kondrashova ◽  
Jussi Lehtonen ◽  
Sami Oikarinen ◽  
Anu-Maaria Hämäläinen ◽  
...  

Early childhood infections have been implicated in the development of immune-mediated diseases, such as allergies, asthma, and type 1 diabetes. We set out to investigate the immunomodulatory effects of early viral infections experienced before the age of one year on the peripheral regulatory T cell population (Treg) and circulating cytokines in a birth-cohort study of Estonian and Finnish infants. We show here a temporal association of virus infection with the expression of FOXP3 in regulatory T cells. Infants with rhinovirus infection during the preceding 30 days had a higher FOXP3 expression in Treg cells and decreased levels of several cytokines related to Th1 and Th2 responses in comparison to the children without infections. In contrast, FOXP3 expression was significantly decreased in highly activated (CD4+CD127−/loCD25+FOXP3high) regulatory T cells (TregFOXP3high) in the infants who had enterovirus infection during the preceding 30 or 60 days. After enterovirus infections, the cytokine profile showed an upregulation of Th1- and Th17-related cytokines and a decreased activation of CCL22, which is a chemokine derived from dendritic cells and associated with Th2 deviation. Our results reveal that immunoregulatory mechanisms are up-regulated after rhinovirus infections, while enterovirus infections are associated with activation of proinflammatory pathways and decreased immune regulation.


Blood ◽  
2006 ◽  
Vol 108 (3) ◽  
pp. 804-811 ◽  
Author(s):  
Marc Beyer ◽  
Joachim L. Schultze

Abstract Increasing evidence supports the existence of elevated numbers of regulatory T cells (Treg cells) in solid tumors and hematologic malignancies. Whereas the biology of CD4+CD25+FOXP3+ Treg cells in murine models seems to be rather straightforward, studies in human diseases are more difficult to interpret due to expression of CD25 on activated effector T cells as well as Treg cells. More importantly, early studies in human tumors were mainly focused on CD4+CD25+ Treg cells lacking interrogation of more specific markers such as FOXP3 expression. Although the increase of Treg cells seems to be a characteristic feature in most tumors, little is known about the molecular and cellular mechanisms responsible for the increase and maintenance of elevated levels of Treg cells in cancer. We will discuss earlier data in the context of recent findings in Treg-cell biology with a particular emphasis on CD4+CD25highFOXP3+ Treg cells in human malignancies.


2021 ◽  
Author(s):  
Emma E. Kraus ◽  
Laura Kakuk-Atkins ◽  
Marissa F. Farinas ◽  
Mathew Jeffers ◽  
Amy E. Lovett-Racke ◽  
...  

Abstract BackgroundMyelin-specific CD4 T effector cells (Teffs), Th1 and Th17 cells, are encephalitogenic in experimental autoimmune encephalomyelitis (EAE), a well-defined murine model of multiple sclerosis (MS) and implicated in MS pathogenesis. Forkhead box O 1 (FoxO1) is a conserved effector molecule in PI3K/Akt signaling and critical in the differentiation of CD4 T cells into T helper subsets. However, it is still unclear whether FoxO1 may be a target for redirecting CD4 T cell differentiation and benefit CNS autoimmunity. MethodsUsing a selective FoxO1 inhibitor AS1842856, we determined the effects of FoxO1 inhibition in regulating myelin-specific Th1 and Th17 cells, and the transcriptional balance of T-bet and Foxp3 in myelin-specific CD4 T cells from EAE mice. The effects of AS1842856 in regulating the encephalitogenicity of myelin-specific T cells and the expansion of human Th1 cells from MS patients were also characterized. Furthermore, we characterized the potential role of FoxO1 in mediating PD-1 signaling in CD4 T cells, critical for regulating Teff and Treg cells. ResultsInhibition of FoxO1 suppressed the differentiation and expansion of Th1 cells. Moreover, the transdifferentiation of Th17 cells into encephalitogenic Th1-like cells was suppressed by FoxO1 inhibition upon reactivation of myelin-specific CD4 T cells from mice with EAE. When FoxO1 was inhibited in myelin-specific CD4 T cells, the transcriptional balance skewed from the Th1 transcription factor T-bet toward the Treg transcription factor Foxp3. Myelin-specific CD4 T cells treated with the FoxO1 inhibitor were less encephalitogenic in adoptive transfer EAE studies compared to control-treated cells. Inhibition of FoxO1 in T cells from MS patients significantly suppressed the expansion of Th1 cells. Furthermore, the immune checkpoint programmed cell death protein-1 (PD-1)-induced Foxp3 expression in CD4 T cells was impaired by FoxO1 inhibition, consistent with a bias toward Treg induction. ConclusionsThese data illustrate an important role of FoxO1 signaling in CNS autoimmunity via regulating autoreactive Teff and Treg balance.


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