scholarly journals MINK1: The missing link between ROS and its inhibition of Th17 cells

2017 ◽  
Vol 214 (5) ◽  
pp. 1205-1206 ◽  
Author(s):  
Gustavo J. Martinez

In this issue of JEM, Fu et al. (https://doi.org/10.1084/jem.20161120) identified the kinase Mink1 as a novel negative regulator of Th17 cell generation. Mink1, activated by reactive oxygen species (ROS), prevents TGF-β activation of Smad2, therefore limiting Th17 cell differentiation.

2021 ◽  
Author(s):  
Ankitha Shetty ◽  
Santosh D. Bhosale ◽  
Subhash Kumar Tripathi ◽  
Tanja Buchacher ◽  
Rahul Biradar ◽  
...  

Dysregulated function of Th17 cells has implications in immunodeficiencies and autoimmune disorders. Th17 cell-differentiation is orchestrated by a complex network of transcription factors, including several members of the activator protein (AP-1) family. Among these, FOSL1 and FOSL2 influence the effector responses of Th17 cells. However, the molecular mechanisms underlying their functions are unclear, owing to the poorly characterized protein interaction networks of these factors. Here, we establish the first interactomes of FOSL1 and FOSL2 in human Th17 cells, using affinity purification–mass spectrometry analysis. In addition to the known JUN proteins, we identified several novel binding partners of FOSL1 and FOSL2. Gene ontology analysis found a major fraction of these interactors to be associated with RNA binding activity, which suggests new mechanistic links. Intriguingly, 29 proteins were found to share interactions with FOSL1 and FOSL2, and these included key regulators of Th17-fate. We further validated the binding partners identified in this study by using parallel reaction monitoring targeted mass spectrometry and other methods. Our study provides key insights into the interaction-based signaling mechanisms of FOSL1 and FOSL2 that potentially govern Th17 cell-differentiation and associated pathologies.


2020 ◽  
Vol 295 (50) ◽  
pp. 17083-17099
Author(s):  
Xiaohui Li ◽  
Liu Chen ◽  
Jingjing Liao ◽  
Jiechen Hui ◽  
Weihui Li ◽  
...  

Reactive oxygen species (ROS) are an unavoidable host environmental cue for intracellular pathogens such as Mycobacterium tuberculosis and Mycobacterium bovis; however, the signaling pathway in mycobacteria for sensing and responding to environmental stress remains largely unclear. Here, we characterize a novel CmtR-Zur-ESX3-Zn2+ regulatory pathway in M. bovis that aids mycobacterial survival under oxidative stress. We demonstrate that CmtR functions as a novel redox sensor and that its expression can be significantly induced under H2O2 stress. CmtR can physically interact with the negative regulator Zur and de-represses the expression of the esx-3 operon, which leads to Zn2+ accumulation and promotion of reactive oxygen species detoxication in mycobacterial cells. Zn2+ can also act as an effector molecule of the CmtR regulator, using which the latter can de-repress its own expression for further inducing bacterial antioxidant adaptation. Consistently, CmtR can induce the expression of EsxH, a component of esx-3 operon involved in Zn2+ transportation that has been reported earlier, and inhibit phagosome maturation in macrophages. Lastly, CmtR significantly contributes to bacterial survival in macrophages and in the lungs of infected mice. Our findings reveal the existence of an antioxidant regulatory pathway in mycobacteria and provide novel information on stress-triggered gene regulation and its association with host–pathogen interaction.


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.


2007 ◽  
Vol 55 (2) ◽  
pp. S348
Author(s):  
M. P. Burns ◽  
S. Pendyala ◽  
I. A. Gorshkova ◽  
D. He ◽  
J. E. Bear ◽  
...  

2009 ◽  
Vol 206 (11) ◽  
pp. 2407-2416 ◽  
Author(s):  
Jyoti Das ◽  
Guangwen Ren ◽  
Liying Zhang ◽  
Arthur I. Roberts ◽  
Xin Zhao ◽  
...  

Interleukin (IL)-17–producing T helper (Th17) cells play a critical role in the pathophysiology of several autoimmune disorders. The differentiation of Th17 cells requires the simultaneous presence of an unusual combination of cytokines: IL-6, a proinflammatory cytokine, and transforming growth factor (TGF) β, an antiinflammatory cytokine. However, the molecular mechanisms by which TGF-β exerts its effects on Th17 cell differentiation remain elusive. We report that TGF-β does not directly promote Th17 cell differentiation but instead acts indirectly by blocking expression of the transcription factors signal transducer and activator of transcription (STAT) 4 and GATA-3, thus preventing Th1 and Th2 cell differentiation. In contrast, TGF-β had no effect on the expression of retinoic acid receptor–related orphan nuclear receptor γt, a Th17-specific transcription factor. Interestingly, in Stat-6−/−T-bet−/− mice, which are unable to generate Th1 and Th2 cells, IL-6 alone was sufficient to induce robust differentiation of Th17 cells, whereas TGF-β had no effect, suggesting that TGF-β is dispensable for Th17 cell development. Consequently, BALB/c Stat-6−/−T-bet−/− mice, but not wild-type BALB/c mice, were highly susceptible to the development of experimental autoimmune encephalomyelitis, which could be blocked by anti–IL-17 antibodies but not by anti–TGF-β antibodies. Collectively, these data provide evidence that TGF-β is not directly required for the molecular orchestration of Th17 cell differentiation.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ping Li ◽  
Zengli Guo ◽  
Yisong Y. Wan

Pathogenic Th17 cells are critically involved in many autoimmune diseases, while non-pathogenic Th17 cells are more immune regulatory. Understanding the mechanisms of the induction and maintenance of pathogenic Th17 cells will benefit the development of therapeutic treatments of related diseases. We have shown that the transforming growth factor-β (TGFβ) induced SKI degradation and dissociation from Smad4 complex is a prerequisite for TGFβ-induced Th17 cell differentiation. However, it is unclear whether and how SKI regulates pathogenic Th17 differentiation, which does not require TGFβ cytokine. Here we showed that SKI expression was downregulated during pathogenic Th17 cell differentiation and the ectopic expression of SKI abrogated the differentiation of pathogenic Th17 cells. Functionally, using a knock-in mouse model, we found ectopic SKI expression specifically in T cells prevented myelin oligodendrocyte glycoprotein peptide (MOG33–55) induced experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis. We further revealed that induced SKI expression in already differentiated pathogenic Th17 cells reduced the maintenance of Th17 program and ameliorated EAE in an adoptive T cell transfer model. Therefore, our study provides valuable insights of targeting SKI to modulate pathogenic Th17 cell function and treat Th17-related diseases.


2019 ◽  
Author(s):  
Bibudha Parasar ◽  
Pamela V. Chang

AbstractT helper 17 (Th17) cells, an important subset of CD4+ T cells, help to eliminate extracellular infectious pathogens that have invaded our tissues. Despite the critical roles of Th17 cells in immunity, how the immune system regulates the production and maintenance of this cell type remains poorly understood. In particular, the plasticity of these cells, or their dynamic ability to trans-differentiate into other CD4+ T cell subsets, remains mostly uncharacterized. Here, we report a synthetic immunology approach using a photo-activatable immune modulator (PIM) to increase Th17 cell differentiation on demand with spatial and temporal precision to help elucidate this important and dynamic process. In this chemical strategy, we developed a latent agonist that, upon photochemical activation, releases a small-molecule ligand that targets the aryl hydrocarbon receptor (AhR) and ultimately induces Th17 cell differentiation. We used this chemical tool to control AhR activation with spatiotemporal precision within cells and to modulate Th17 cell differentiation on demand by using UV light illumination. We envision that this approach will enable an understanding of the dynamic functions and behaviors of Th17 cells in vivo during immune responses and in mouse models of inflammatory disease.


2022 ◽  
Author(s):  
Dan Liang ◽  
Jun Huang ◽  
Zhuang Li ◽  
Yunwei Hu ◽  
Zuoyi Li ◽  
...  

Abstract Background Melatonin, an indoleamine produced by the pineal gland, plays a pivotal role in maintaining circadian rhythm homeostasis. Recently, the strong antioxidant and anti-inflammatory properties of melatonin have attracted attention of researchers. We evaluated the therapeutic efficacy of melatonin in experimental autoimmune uveitis (EAU), which is a representative animal model of human autoimmune uveitis. Methods EAU was induced in mice via immunization with the peptide interphotoreceptor retinoid binding protein 1-20 (IRBP1−20). melatonin was then administered via intraperitoneal injection to induce protection against EAU. With EAU induction for 14 days, clinical and histopathological scores were employed to evaluate the disease progression. T lymphocytes accumulation, the expression of inflammatory cytokines in the retinas were assessed via flow cytometry and RT-PCR. In vivo and in vitro experiments, T helper 1 (Th1), T helper 17 (Th17) and regulatory T (Treg) cells were detected via flow cytometry, the level reactive oxygen species(ROS) from CD4+ cells were tested via flow cytometry, and the expression of thioredoxin-interacting protein (TXNIP) and hypoxia-inducible factor 1 alpha (HIF-1α)proteins were also quantified via western blot analysis, to elucidate the mechanism of melatonin inhibiting EAU. Results Melatonin treatment resulted in notable attenuation of ocular inflammation in EAU mice, evidenced by decreasing optic disc edema, few signs of retinal vasculitis, and minimal retinal and choroidal infiltrates. Mechanistic studies revealed that melatonin restricted the proliferation of peripheral Th1 and Th17 cells and potentiated Treg cells by suppressing their transcription factors. In vitro studies corroborated that melatonin restrains the polarization of retina-specific T cells towards Th17 and Th1 cells in addition to enhancing the proportion of Treg cells. Pretreatment of retina-specific T cells with melatonin failed to induce EAU in naïve recipients. Furthermore, the ROS/ TXNIP/ HIF-1α pathway was shown to mediate the therapeutic effect of melatonin in EAU. Conclusions Melatonin regulates autoimmune T cells by restraining effector T cells and facilitating Treg generation, indicating that melatonin could be a hopeful treatment alternative for autoimmune uveitis.


Sign in / Sign up

Export Citation Format

Share Document