RORγt Expression Research Articles

Repurposing the anthelmintic praziquantel to treat psoriasis.

The anthelmintic drug praziquantel has been used as a standard treatment for schistosomiasis for over 40 years. This study aimed to repurpose praziquantel to treat psoriasis. Psoriasis-like skin inflammation was induced in mice (C57 and Balb/C) by topical application of imiquimod or intradermal injection of recombinant IL-23. Praziquantel was either orally or topically administered during the psoriasis induction period. Mice treated with either oral or topical praziquantel exhibited markedly improved psoriasiform skin symptoms when compared with control mice, as judged by disease severity score, epidermal thickening, inflammatory cell infiltration and spleen size. Flow cytometric analysis of infiltrating immune cells from mouse skin displayed reduced infiltration of Th17 cells. In vitro experiments revealed that praziquantel inhibited STAT3 phosphorylation and RORγt expression in splenic CD4+ T-cells. Praziquantel also decreased STAT3 phosphorylation in HEK-A/F cells. Down-regulation of STAT3 phosphorylation in these cells accounts for the decreased number of Th17 cells and keratinocytes. These results provide the first preclinical evidence that praziquantel may effectively treat psoriasis, and suggest that praziquantel alleviates symptoms in mice by inhibiting STAT3 phosphorylation, thereby suppressing Th17 immune responses.

Huganbuzure Granule Attenuates Concanavalin-A-Induced Immune Liver Injury in Mice via Regulating the Balance of Th1/Th2/Th17/Treg Cells and Inhibiting Apoptosis.

In Uygur medicine, Huganbuzure granule (HBG) is one of the classical prescriptions for liver protection. However, its role in immune liver injury remains unknown. This study evaluates the effect of HBG on concanavalin-A- (ConA-) induced immune liver injury and investigates its protective underlying mechanism. BALB/c mice were randomly divided into five groups (n = 24 mice per group): control, ConA, 1.6 g/kg HBG + ConA, 3.2 g/kg HBG + ConA, and 6 mg/kg prednisolone + ConA. HBG was intragastrically administrated once daily for ten consecutive days, prior to ConA (20 mg/kg) injection. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), superoxide dismutase (SOD), and malondialdehyde (MDA) in mouse serum were measured after ConA injection. Moreover, liver-related mRNA levels were evaluated by qPCR. The detection of liver-related proteins was assessed by immunohistochemistry and western blot analysis. Compared with the ConA group, HBG reduced the mRNA expression of IL-17A and IFN-γ and the protein expression of T-bet and ROR-γt. In addition, HBG increased the mRNA expression of IL-4 and TGF-β and protein expression of GATA3 and Foxp3, indicating that HBG regulated the balance of Th1/Th2 and Th17/Treg. Furthermore, HBG alleviated immune liver injury by reducing oxidative stress, inhibiting apoptosis, and decreasing the expression of p-JNK, p-ERK, p-p38, p-JAK1, p-STAT1, p-STAT3, and IRF1. Our data suggested that HBG attenuated ConA-induced immune liver injury by regulating the immune balance and inhibiting JAK1/STATs/IRF1 signaling, thereby reducing apoptosis induced by JNK activation. The findings indicate that HBG may be a promising drug for immune liver injury.

RORγt inhibitor SR1001 alleviates acute pancreatitis by suppressing pancreatic IL-17-producing Th17 and γδ-T cells in mice with ceruletide-induced pancreatitis.

The management of acute pancreatitis (AP) remains a challenge to clinicians worldwide for limited effective interventions. Retinoid orphan receptor gamma t (RORγt) is a therapeutic target for several diseases; however, it is unclear whether inhibiting RORγt can ameliorate AP. The relative expression of RORγt, IL‐17 and IL‐23 in the peripheral blood mononuclear cells of AP patients was measured by RT‐PCR. An AP mouse model was induced by ceruletide, and SR1001 was injected before ceruletide administration. RORγt+ cells, T helper 17 cells (Th17), regulatory T cells (Tregs) and γδ T cells were assessed in the pancreas and spleen by flow cytometry. Higher RORγt expression in patients indicated the potential role of RORγt in AP progression. Analyses of the IL‐17/IL‐23 axis confirmed its role. SR1001 significantly alleviated AP histologically in the mouse model. Serum levels of amylase, IL‐6, TNFalpha, IL‐17 and IL‐23 decreased upon SR1001 treatment. SR1001 selectively decreased the number of RORγt+, Th17, Tregs and γδ T cells in the pancreas but not the spleen. Collectively, these results showed that SR1001 exerted therapeutic effects on AP by suppressing IL‐17‐secreting Th17 and γδ T cells in the pancreas. Thus, SR1001 may be a promising drug for the treatment of AP in the clinic.

STAT5 Represses a STAT3-Independent Th17-like Program during Th9 Cell Differentiation.

IL-9-producing Th cells, termed Th9 cells, contribute to immunity against parasites and cancers but have detrimental roles in allergic disease and colitis. Th9 cells differentiate in response to IL-4 and TGF-β, but these signals are insufficient to drive Th9 differentiation in the absence of IL-2. IL-2-induced STAT5 activation is required for chromatin accessibility within Il9 enhancer and promoter regions and directly transactivates the Il9 locus. STAT5 also suppresses gene expression during Th9 cell development, but these roles are less well defined. In this study, we demonstrate that human allergy-associated Th9 cells exhibited a signature of STAT5-mediated gene repression that is associated with the silencing of a Th17-like transcriptional signature. In murine Th9 cell differentiation, blockade of IL-2/STAT5 signaling induced the expression of IL-17 and the Th17-associated transcription factor Rorγt. However, IL-2-deprived Th9 cells did not exhibit a significant Th17- or STAT3-associated transcriptional signature. Consistent with these observations, differentiation of IL-17-producing cells under these conditions was STAT3-independent but did require Rorγt and BATF. Furthermore, ectopic expression of Rorγt and BATF partially rescued IL-17 production in STAT3-deficient Th17 cells, highlighting the importance of these factors in this process. Although STAT3 was not required for the differentiation of IL-17-producing cells under IL-2-deprived Th9 conditions, their prolonged survival was STAT3-dependent, potentially explaining why STAT3-independent IL-17 production is not commonly observed in vivo. Together, our data suggest that IL-2/STAT5 signaling plays an important role in controlling the balance of a Th9 versus a Th17-like differentiation program in vitro and in allergic disease.

Lung eosinophils elicited during allergic and acute aspergillosis express RORγt and IL-23R but do not require IL-23 for IL-17 production.

Exposure to the mold, Aspergillus, is ubiquitous and generally has no adverse consequences in immunocompetent persons. However, invasive and allergic aspergillosis can develop in immunocompromised and atopic individuals, respectively. Previously, we demonstrated that mouse lung eosinophils produce IL-17 in response to stimulation by live conidia and antigens of A. fumigatus. Here, we utilized murine models of allergic and acute pulmonary aspergillosis to determine the association of IL-23, IL-23R and RORγt with eosinophil IL-17 expression. Following A. fumigatus stimulation, a population of lung eosinophils expressed RORγt, the master transcription factor for IL-17 regulation. Eosinophil RORγt expression was demonstrated by flow cytometry, confocal microscopy, western blotting and an mCherry reporter mouse. Both nuclear and cytoplasmic localization of RORγt in eosinophils were observed, although the former predominated. A population of lung eosinophils also expressed IL-23R. While expression of IL-23R was positively correlated with expression of RORγt, expression of RORγt and IL-17 was similar when comparing lung eosinophils from A. fumigatus-challenged wild-type and IL-23p19-/- mice. Thus, in allergic and acute models of pulmonary aspergillosis, lung eosinophils express IL-17, RORγt and IL-23R. However, IL-23 is dispensable for production of IL-17 and RORγt.

Extract From Tetrastigma hemsleyanum Leaf Alleviates Pseudomonas aeruginosa Lung Infection: Network Pharmacology Analysis and Experimental Evidence.

Tetrastigma hemsleyanum Diels & Gilg (T. hemsleyanum) has attracted much attention due to its ability on pneumonia, bronchitis, and immune-related diseases, while its functional components and underlying mechanism of action on pneumonia have not been fully elucidated. Herein, we used a systematic network pharmacology approach to explore the action mechanism of T. hemsleyanum leaf in the treatment of pneumonia. In this study, the results of network pharmacology demonstrated that there were 34 active components and 80 drug–disease targets in T. hemsleyanum leaf, which were strongly in connection with signal transduction, inflammatory response, and the oxidation–reduction process. Subsequently, a mouse model of pneumonia induced by Pseudomonas aeruginosa (P. aeruginosa) was established to validate the predicted results of network pharmacology. In the animal experiments, aqueous extract of T. hemsleyanum leaf (EFT) significantly attenuated the histopathological changes of lung tissue in P. aeruginosa–induced mice and reduced the number of bacterial colonies in BALFs by 96.84% (p < 0.01). Moreover, EFT treatment suppressed the increase of pro-inflammatory cytokines IL-17, IL-6, and TNF-α in lung tissues triggered by P. aeruginosa, which led to the increase of Th17 cells (p < 0.05). High concentration of EFT treatment (2.0 g/kg) obviously increased the anti-inflammatory cytokine levels, accompanied by the enhancement of Treg proportion in a dose-dependent manner and a notable reversal of transcription factor RORγt expression. These findings demonstrated that network pharmacology was a useful tool for TCM research, and the anti-inflammatory effect of EFT was achieved by maintaining Th17/Treg immune homeostasis and thereby suppressing the inflammatory immune response.

Bergenin, a PPARγ agonist, inhibits Th17 differentiation and subsequent neutrophilic asthma by preventing GLS1-dependent glutaminolysis.

Bergenin is a natural PPARγ agonist that can prevent neutrophil aggregation, and often be used in clinics for treating respiratory diseases. Recent data show that Th17 cells are important for neutrophil aggregation and asthma through secreting IL-17A. In this study, we investigated the effects of bergenin on Th17 differentiation in vitro and subsequent neutrophilic asthma in mice. Naïve T cells isolated from mouse mesenteric lymph nodes were treated with IL-23, TGF-β, and IL-6 to induce Th17 differentiation. We showed that in naïve T cells under Th17-polarizing condition, the addition of bergenin (3, 10, 30 μM) concentration-dependently decreased the percentage of CD4+ IL-17A+ T cells and mRNA expression of specific transcription factor RORγt, and function-related factors IL-17A/F, IL-21, and IL-22, but did not affect the cell vitality and apoptosis. Furthermore, bergenin treatment prevented GLS1-dependent glutaminolysis in the progress of Th17 differentiation, slightly affected the levels of SLC1A5, SLC38A1, GLUD1, GOT1, and GPT2. Glutamine deprivation, the addition of glutamate (1 mM), α-ketoglutarate (1 mM), or GLS1 plasmid all significantly attenuated the above-mentioned actions of bergenin. Besides, we demonstrated that bergenin (3, 10, and 30 μM) concentration-dependently activated PPARγ in naïve T cells, whereas PPARγ antagonist GW9662 and siPPARγ abolished bergenin-caused inhibition on glutaminolysis and Th17 differentiation. Furthermore, we revealed that bergenin inhibited glutaminolysis by regulating the level of CDK1, phosphorylation and degradation of Cdh1, and APC/C-Cdh1-mediated ubiquitin-proteasomal degradation of GLS1 after activating PPARγ. We demonstrated a correlation existing among bergenin-affected GLS1-dependent glutaminolysis, PPARγ, "CDK1-APC/C-Cdh1" signaling, and Th17 differentiation. Finally, the therapeutic effect and mechanisms for bergenin-inhibited Th17 responses and neutrophilic asthma were confirmed in a mouse model of neutrophilic asthma by administration of GW9662 or GLS1 overexpression plasmid in vivo. In conclusion, bergenin repressed Th17 differentiation and then alleviated neutrophilic asthma in mice by inhibiting GLS1-dependent glutaminolysis via regulating the "CDK1-APC/C-Cdh1" signaling after activating PPARγ.

Innate lymphoid cells and cancer: Role in tumor progression and inhibition.

Innate lymphoid cells (ILCs), a critical component of the immune system, have recently been nominated as emerging players associated with tumor progression and inhibition. ILCs are classified into five groups: natural killer (NK) cells, ILC1s, ILC2s, ILC3s, and lymphoid tissue inducer (LTis) cells. NK cells and ILC1s are mainly involved in antitumor activities due to their cytotoxic and cytokine production capabilities, respectively. The current understanding of the heterogeneous behavior of ILC2s and ILC3s in tumors is limited and incomplete. Mostly, their dual roles are modulated by their resident tissues, released cytokines, cancer types, and plasticity. Based on overlap RORγt and cytokine expression, the LTi cells were previously considered part of the ILC3s ontogeny, which are essential for the formation of the secondary lymphoid organs during embryogenesis. Indeed, these facts highlight the urgency in understanding the respective mechanisms that shape the phenotypes and responses of ILCs, either on the repressive or proliferative side in the tumor microenvironment (TME). This review aims to provide an updated view of ILCs biology with respect to tumorigenesis, including a description of ILC plasticity, their interaction with other immune cells and communication with components of the TME. Taken together, targeting ILCs for cancer immunotherapy could be a promising approach against tumors that needs to be further study.

Quantities and Functions of NK Cells in Severe Aplastic Anemia

IntroductionSevere aplastic anemia (SAA) is an autoimmune disease characterized by bone marrow failure. Natural killer (NK) cells are a key component in the innate immunity and adaptive immune. Our team have previously investigated the quantity and primary functions of NK in SAA. Here, we tend to present the extensive study on the roles NK has played in SAA.MethodsWe successively collected patients with untreated SAA, SAA response to immunosuppressive therapy (SAA-CR+PR), and healthy controls (HC) as research participants. Quantities of circulating NK and their subsets (CD56bright NK and CD56dim NK) were identified, the expressions of surface receptors,intracelluar protein and intracellular cytokines were analyzed by flow cytometry (FCM). Plasmatic IL-2 and IL-12 levels were measured by ELISA. NK cells were cultured with K562 cells. The apoptotic rate of K562 was measured to detect killing functions of NK. NK cells were co-cultured with CD4+ T , CD8+ T and myeloid Dendritic Cells (mDCs) from SAA. Quantities of Th1, Th2, Th17 and Treg, expressions of perforin and Granzyme B in CD8+ T cells and expressions of CD80 and CD86 on mDCs were analyzed by FCM. The mRNA expressions of T-bet, GATA3, RORγt and FOXP3 were measured by qRT-PCR. Proliferation rates of CD8+ T cells and mDC were detected by CCK-8. PeripheralNK cells were sorted and cultured with rhIL-2 and rhIL-12. The supernatants were detected for the cytokines produced by NK. The cytokines and their upstream signal molecules were analyzed by qRT-PCR and Western Blot. Finally, we investigated the quantities and the surface receptors of NK using the mouse model of lymphocyte infusion-induced bone marrow failure to confirm their functions.ResultsThe percentages of NK/lymphocytes and CD56brightNK/NK in SAA were significantly lower than in HC. The absolute number of NK cells in SAA was positively correlated with PLT, absolute number of Reticular cells (Ret) and percentage of Ret (p <0.01). NK cells in SAA expressed higher levels of NKp46, CD158a and perforin compared with those in HC. The percentage of DNAM-1+ NK was higher than that in HC (p=0.007). After PMA stimulation, NK cells in SAA produced lower level of IFN-γ and higher level of IL-10 and TGF-β compared with those in HC. The plasmatic levels of IL-2 and IL-12 in SAA were higher than in SAA-CR+PR and HC. The apoptotic rate of K562 cells when co-cultured with NK cells (1:1) was significantly higher than in HC.IL-2stimulatedNK cells from SAA expressed higher percentage of CD107a+ than from HC (p=0.017) when co-cultured with autologous activated CD4+T cells. After co-cultured with NK cells from SAA, the ratio of Th1/Th2 and Th17/Treg was decreased. The expressions of perforin and Granzyme B in CD8+ T cells were higher when co-cultured with NK from HC than in non-coculture group. The cell inhibition rate of mDCs when co-cultured with NK from SAA was higher than from HC. The expression of CD80 on mDCs when co-cultured with NK from HC was up-regulated.NK cells from SAA secreted lower level of IFN-γ, expressed lower levels of IFN-γ and STAT4 mRNA and phosphorylated STAT4. NK cells from SAA secreted higher levels of IL-10 and TGF-β, expressed higher levels of IL-10, TGF-β and p38 mRNA and phosphorylated p38. Bone marrow failure mouse model showed the quantities of NK cells weredecreased, the expression of NKG2A on NK was elevated. After the treatment of Cyclosporin A (CsA), the quantities NK cells recovered, the expression of NKG2D was elevated while NKG2A was not changed.ConclusionsInsufficient amount of NK cells was shown in SAA patients. The lower quantity of NK cells the patients had,the more severe the disease was. NK cells in SAA were functionally activated and exhibited strong killing abilities. NK cells in SAA produced less Type Ⅰ cytokines and more Type Ⅱ cytokines. Plasmatic levels of IL-2 and IL-12 were elevated in SAA. NK cells from SAA mediated in the differentiation of CD4+ T cells by influencing the balance of Th1/Th2 and Th17/Treg. NK cells from SAA might be able to down-regulate the cytotoxicity activity of CD8+ T cells and the expressions of co-stimulatory molecules on mDCs. The cell signal pathway JAK-STAT4-IFN-γ in NK cells from SAA was down-regulated while pathway p38 MAPK-IL10/TGF-β was up-regulated. Bone marrow failure mouse model suggested the impairment of both quantities and activating status of NK. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

NKG2D Negatively Regulates CD4 T Cells in Allo-Response in Mice

NKG2D is a C-type lectin-like receptor which mainly expresses on mouse NK, activated CD8 and some γδ T cells. NKG2D is also found to express on human and mouse CD4 T cells, but the role of NKG2D in CD4 T cells is essentially unknown. We asked what subsets of CD4 T cells could express NKG2D; we activated and polarized CD4 T cells into Th0, Th1,Th2, Th17 and Foxp3+ Tregs in vitro and measured NKG2D expression on those subsets. We found that only a proportion of Th1 cells expressed NKG2D, whereas little or no NKG2D was expressed on other subsets of T cells. In a mixed lymphocyte reaction (MLR) assay, NKG2D was induced on a subset of CD4 T cells after stimulation with allogeneic antigen presenting cells (APCs) (Figure 1A). NKG2D+CD4+ T cells expressed higher levels of LAG-3, CD49b, CD80, FasL and PD-L1 (Figure 1B) and secreted more IL-10 and IFN-γ than NKG2D- CD4+ T cells (Figure 1C).Previous reports by others showed that NKG2D on NK and activated CD8 T cells contributing to graft versus host disease (GVHD) pathogenesis have been well-established, but the expression and function of NKG2D on CD4 T cells in GVHD development are unknown.To address these questions, we utilized a CD4-driven, MHC-mismatched aGVHD model of allogeneic bone marrow transplantation (allo-BMT), C57BL/6 to BALB/c. We monitored the development of NKG2D+CD4+ T cells in allogeneic recipients. We observed that NKG2D was continuously induced on CD4 T cells during the whole aGVHD process - gradually increased, peaked on day 14 and then slowly decreased after allo-BMT. By comparing the severity of aGVHD in recipients transferred with WT versus NKG2D-/- CD4 T cells. We observed that recipients transferred with NKG2D-/- CD4 T cells showed more severe GVHD demonstrated by a higher lethality (Figure 1D) and more severe diarrhea compared to WT counterpart. Mechanistically, NKG2D-/- CD4 T cells had a higher capacity of migrating to gut and liver than WT CD4 T cells reflected by the higher expression of α4β7 and CXCR3. Furthermore, NKG2D+CD4+ T cells secreted less proinflammatory cytokine IL-17 and more anti-inflammatory cytokine IL-10. Strikingly, NKG2D expression coincided with T-bet, but excluded RORγt or Foxp3 expression of CD4 T cells. Given NKG2D+CD4+ T cells expressed regulatory markers and secreted IL-10 and IFN-γ; we hypothesized that NKG2D+CD4+ T cells may serve as suppressive cells (e.g. Tr1 cells). To test this hypothesis, we sorted NKG2D+CD4+ and NKG2D-CD4+ T cells from recipients of allogeneic BMT, and performed in vitro suppressive assay. We observed that NKG2D+CD4+ T cells had a higher suppressive activity than NKG2D-CD4+ T cells. (Figure 1E)Taken together, the current work demonstrates that NKG2D may serve as a negative regulator on CD4 T cells, and NKG2D+CD4+ subset can function as a regulatory cell subset in the development of GVHD after allo-BMT. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Rapid, Treatment-Sensitive Graft Infiltration By Novel Lineage Negative RORγt+ Hematopoietic Cells

Using in vivo imaging and cell phenotype monitoring, we identified a previously uncharacterized Lineage-RORγt+ early hematopoietic cell population with multi-lineage potential infiltrating allograft, syngeneic and sham transplant sites. They are distinctly different from Th17 cells, TCR γδ T, and iNKT cells. Some Lineage-RORγt+ infiltrating cells are CD127+ or NKp46+, and therefore, are likely group 3 innate lymphoid cells (ILC3s). ILC3 are known to have a powerful effect on the conduct of inflammation. Additionally, some of these Lineage-RORgt+ cells express classical hematopoietic stem cells traits “LSK” (Lineage-Sca-1+c-kit+). The genetic ablation of RORγt expression and treatment with alpha1 anti-trypsin (AAT), a treatment that reduces inflammation, also reduces infiltration by RORγt+ cells at the graft site. Taken together, these data suggest an important role for RORγt+ cells in the allograft response.Jiafan Liu and Zhenni Zhao are the co-first author for the abstract DisclosuresNo relevant conflicts of interest to declare.

Immunomodulatory effect of psoriasis-derived dermal mesenchymal stem cells on TH1/TH17 cells.

T cell-mediated inflammation plays an important role in the development of psoriasis. Mesenchymal stem cells (MSCs) are a population of multipotent cells that regulate the T cell-mediated immune response. To investigate the effects of psoriatic dermal mesenchymal stem cells (p-DMSCs) on proliferation, apoptosis and differentiation of T cells. p-DMSCs and normal DMSCs (n-DMSCs) were isolated from psoriatic skin and normal healthy controls, respectively, and co-cultured with activated T cells isolated from healthy volunteers using a Transwell system. Proliferation and apoptosis of T cells were assessed by cell count and flow cytometry, respectively. Expression levels of transcription factors associated with subtypes of T cells and cytokines were measured by qRT-PCR and western blot. Both p-DMSCs and n-DMSCs inhibited T cell proliferation and cytokine production. Similarly, the presence of p-DMSCs and n-DMSCs decreased the expression levels of both T-bet and ROR-γt in T cells. However, n-DMSCs exhibited a stronger inhibitory effect than p-DMSCs on T cell proliferation, cytokine production, and T-bet and ROR-γt expression. These results suggest that the effect of p-DMSCs on T cell function could contribute, at least in part, to the pathogenesis of psoriasis.

Traffic-related PM2.5 and diverse constituents disturb the balance of Th17/Treg cells by STAT3/RORγt-STAT5/Foxp3 signaling pathway in a rat model of asthma

Water-soluble ions (WSI) and organic extract (OE) in traffic-related particulate matter with aerodynamic diameters ≤ 2.5 μm (TRPM2.5) are potential risk factors for asthma exacerbation. Although CD4+ T lymphocytes mediated immune response is involved in the pathogenesis of asthma, the effect of WSI-TRPM2.5 and OE-TRPM2.5 on the balance of Th17/Treg cells in asthma remains poorly understood. In this study, the ovalbumin (OVA)-sensitized rats were repeatedly exposure to TRPM2.5 (3 mg/kg·bw), WSI-TRPM2.5 (1.8 mg/kg·bw, 7.2 mg/kg·bw) and OE-TRPM2.5 (0.6 mg/kg·bw, 2.4 mg/kg·bw) every three days for five times. The inflammation response and hyperemia edema were observed in the lung and trachea tissues. DNA methylation levels of STAT3 and RORγt genes in rats with WSI-TRPM2.5 and OE-TRPM2.5 treatment were decreased. DNA methylation level in STAT5 gene tended to decrease, with no change observed on Foxp3 expression. WSI-TRPM2.5 and OE-TRPM2.5 enhanced the mRNA and protein expression of STAT3 and RORγt while inhibited the expression of STAT5 and Foxp3, which may contribute to the imbalance of Th17/Treg cells (P < 0.05). More importantly, recovered balance of Th17/Treg cell subsets, upregulated p-STAT5 and Foxp3 expression and reduced p-STAT3 and RORγt levels were observed after 5-Aza treatment. Our results demonstrate that the STAT3/RORγt-STAT5/Foxp3 signaling pathway is involved in asthma exacerbation induced by WSI-TRPM2.5 and OE-TRPM2.5 through disrupting the balance of Th17/Treg cells. The alteration of DNA methylation of STAT3, STAT5, and RORγt genes may be involved in asthma exacerbation as well.

Soufeng sanjie formula alleviates collagen-induced arthritis in mice by inhibiting Th17 cell differentiation

BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disease. Soufeng sanjie formula (SF), which is composed of scolopendra (dried body of Scolopendra subspinipes mutilans L. Koch), scorpion (dried body of Buthus martensii Karsch), astragali radix (dried root of Astragalus membranaceus (Fisch.) Bge), and black soybean seed coats (seed coats of Glycine max (L.) Merr), is a traditional Chinese prescription for treating RA. However, the mechanism of SF in treating RA remains unclear. This study was aim to investigate the anti-arthritic effects of SF in a collagen-induced arthritis (CIA) mouse model and explore the mechanism by which SF alleviates arthritis in CIA mice.MethodsFor in vivo studies, female DBA/1J mice were used to establish the CIA model, and either SF (183 or 550 mg/kg/day) or methotrexate (MTX, 920 mg/kg, twice/week) was orally administered to the mice from the day of arthritis onset. After administration for 30 days, degree of ankle joint destruction and serum levels of IgG and inflammatory cytokines were determined. The balance of Th17/Treg cells in the spleen and lymph nodes was analyzed using flow cytometry. Moreover, the expression levels of retinoic acid receptor-related orphan nuclear receptor (ROR) γt and phosphorylated STAT3 (pSTAT3, Tyr705) in the spleen were detected by immunohistochemistry. Furthermore, the effect of SF on Th17 cells differentiation in vitro was investigated in CD4+ T cells under Th17 polarization conditions.ResultsSF decreased the arthritis score, ameliorated paw swelling, and reduced cartilage loss in the joint of CIA mice. In addition, SF decreased the levels of bovine collagen-specific IgG in sera of CIA mice. SF decreased the levels of inflammatory cytokines (TNF-α, IL-6, and IL-17A) and increased the level of IL-10 both in the sera and the joint of CIA mice. Moreover, SF treatment rebalanced the Th17/Treg ratio in the spleen and lymph nodes of CIA mice. SF also reduced the expression levels of ROR γt and pSTAT3 (Tyr705) in the spleen of CIA mice. In vitro, SF treatment reduced Th17 cell generation and IL-17A production and inhibited the expression of RORγt, IRF4, IL-17A, and pSTAT3 (Tyr705) under Th17 polarization conditions.ConclusionsOur results suggest that SF exhibits anti-arthritic effects and restores Th17/Treg homeostasis in CIA mice by inhibiting Th17 cell differentiation.

Moderately pathogenic maternal influenza A virus infection disrupts placental integrity but spares the fetal brain

Maternal infection during pregnancy is a known risk factor for offspring mental health disorders. Animal models of maternal immune activation (MIA) have implicated specific cellular and molecular etiologies of psychiatric illness, but most rely on pathogen mimetics. Here, we developed a mouse model of live H3N2 influenza A virus (IAV) infection during pregnancy that induces a robust inflammatory response but is sublethal to both dams and offspring. We observed classic indicators of lung inflammation and severely diminished weight gain in IAV-infected dams. This was accompanied by immune cell infiltration in the placenta and partial breakdown of placental integrity. However, indications of fetal neuroinflammation were absent. Further hallmarks of mimetic-induced MIA, including enhanced circulating maternal IL-17A, were also absent. Respiratory IAV infection did result in an upregulation in intestinal expression of transcription factor RORγt, master regulator of a subset of T lymphocytes, TH17 cells, which are heavily implicated in MIA-induced etiologies. Nonetheless, subsequent augmentation in IL-17A production and concomitant overt intestinal injury was not evident. Our results suggest that mild or moderately pathogenic IAV infection during pregnancy does not inflame the developing fetal brain, and highlight the importance of live pathogen infection models for the study of MIA.

Ineffective CD4 T cell polarization reveals a novel immune evasion target of Borrelia burgdorferi

Abstract Appropriate polarization of effector CD4 T cells is essential for eliminating invading pathogens. Borrelia burgdorferi (Bb), the spirochetal agent of Lyme disease, evades immune clearance in infected mice and humans, establishing bacterial persistence. Here we aimed to explore the functionality of CD4 T cell as a possible target of Borrelia-induced immune evasion. In response to Bb infection, CD4 T cell polarization is considered to be Th1 dominant. However, when we stimulated CD4 T cells from Bb infected mice ex vivo with Bb surface Ag Arthritis Related Protein (Arp), we were unable to detect IFNγ, prompting us to re-examine the polarization state of lymph node and blood effector CD4 T cells throughout Bb infection by quantitative RT-PCR and flow cytometry. In contrast to prevailing views, we found only modest numbers of Th1-polarized activated CD4 T cells, as measured by expression of Tbet (Tbx21), and little to no induction of Ifng, including in Bb-specific CD4 T cells, identified by a novel I-Ab tetramer to Arp. This could not be explained by enhanced polarization to Th2 or Th17, as GATA-3 and RORγt expression were also largely absent. Nor could it be explained by polarization at a T cell effector site, the skin, as skin-resident T cells also showed no polarization even 4 months after infection. Furthermore, Th1 polarization was not necessary for controlling bacterial dissemination, as Bb infection of Tbet−/− mice showed significant reductions in Borrelia numbers in the tibiotarsal joints, which correlated with enhanced Th17 polarization as measured by RORγt expression. Together, our data demonstrate a failure of CD4 T cell polarization after Bb infection, indicating effector CD4 T cell polarization as a novel target of Bb immune evasion.

Vitamin E and selenium improve mesenchymal stem cell conditioned media immunomodulatory effects.

Mesenchymal stem cells (MSCs) with immunoregulatory properties affect immune systems. Many studies showed that antioxidants such as vitamin E (Vit E) and selenium (Se) could improve stem cells survival. This study aims to investigate the effects of MSC conditioned media (CM) treated with Vit E and Se on immune cells. MSCs were isolated and cultured with Vit E and Se. Immature dendritic cells (DCs) and peripheral blood mononuclear cells (PBMCs) were cultured with MSC CM treated with Vit E and Se. The expression of HLA-DR, CD86, CD40, and CD83 on mature DC were evaluated. DC supernatant and PBMCs supernatant was collected for the study of TGF-β, IL-10, and IL-12. PBMCs evaluated for the expression of T-bet, GATA3, RORγt, and FOXP3. MSC CM increased CD40 on myeloid DC (mDC). CD40 has been decreased in DC treated with MSC (Vit E) and MSC (Se) CM. HLA-DR expression on DCs and IL-12 level were significantly reduced in MSC (Vit E) CM. IL-10 concentration increased in DCs treated with MSC (Vit E) and MSC (Se) CM. Treatment of PBMCs with MSC CM decreased IL-10 level, FOXP3, and RORγt expression. On the other hand, the MSC (Vit E) CM and MSC (Se) CM decreased the IL-10 level and increased IL-12, T-bet, and RORγt. According to the results, the treatment of MSC with Vit E and Se enhanced the ability of MSCs to inhibit DCs and improved immunomodulatory effects. Concerning the effect of MSC on PBMC, it seems that it increased RORγt expression through monocytes.

Juglone regulates gut microbiota and Th17/Treg balance in DSS-induced ulcerative colitis

Juglone, mainly isolates from the green walnut husks of Juglans mandshurica, exhibits anti-cancer and anti-inflammaroty activities. But its protection on ulcerative colitis (UC) has never been explored. In this study, we first evaluated whether juglone ameliorated UC, and investigated its effects on gut microbiota and Th17/Treg balance in DSS-induced UC mice model. The model was established by administrating 2.7% DSS for seven days. Juglone was given daily by gavage for ten days, once a day. The disease activity index (DAI) decrease and pathological characteristics improvement demonstrated that the UC in mice was alleviated by juglone. Juglone treatment significantly inhibited the protein levels of IL-6, TNF-α and IL-1β, improved the protein expression of IL-10. In addition, juglone altered microbial diversity and gut microbiota composition, including the enhancement of the ratio of Firmicutes to Bacteroidota and the abundance of Actinobacteriota, and decrease of the abundance of Verrucomicrobiota. Juglone treatment also inhibited the protein expressions of IL-6, STAT3 and RORγt, meanwhile improved the protein level of FOXP3. Furthermore, juglone inhibited Th17 development and increased Treg generation, beneficial to Th17/Treg balance. Together, we herein provided the first evidence to support that juglone, especially the high dose, possibly protected mice against UC by modulating gut microbiota and restoring Th17/Treg homeostasis.

Intervention mechanism of moxa-cone moxibustion at Shu- and Mu-acupoints on the expression of RORγt/Foxp3 in asthma mice: an analysis based on PI3K signaling pathway

To explore the effect of moxa-cone moxibustion at "Feishu" (BL13) and "Zhongfu" (LU1) on the contents of related inflammatory factors in serum and bronchoalveolar lavage fluid (BALF), and the expression of phosphatidy-linositol-3-kinase (PI3K), retinoic acid related orphan receptor γt (RORγt) and fork/wing helix transcription factor 3 (Foxp3) in lung tissue in asthma mice. Sixty male Balb/c mice were divided into normal, model, LY294002 (an inhibitor of PI3K, LY), electroacupuncture (EA) and moxa-cone moxibustion (moxibustion) groups (n=12 in each group). The asthma model was established by intraperitoneal injection of ovalbumin sensitization. The mice in the LY group were injected with LY 294002 (7.5 mg/kg) via the tail vein. EA or moxa-cone moxibustion was applied at BL13 and LU1 in the EA or moxibustion group once daily for 2 weeks. The levels of immunoglobulin E (IgE), interleukin-4 (IL-4) and interferon-γ (IFN-γ) in serum and BALF were detected by enzyme-linked immunosorbent assay. The expressions of PI3K, RORγt and Foxp3 in lung tissue were detected by real-time fluorescent quantitative polymerase chain reaction (QRT PCR) and immunohistochemistry. Compared with the normal group, the levels of IgE and IL-4 in serum and BALF, the expressions of PI3K and RORγt mRNA and protein in lung tissue were significantly increased (P<0.01), while the levels of IFN-γ, and the expressions of Foxp3 mRNA and protein were significantly reduced (P<0.01) in the model group. Compared with the model group, the levels of IgE and IL-4 in serum and BALF, the expressions of PI3K and RORγt mRNA and protein in lung tissue were significantly decreased (P<0.01, P<0.05), and the levels of IFN-γ in serum and BALF, the expressions of Foxp3 mRNA and protein in lung tissue were significantly increased (P<0.01) in the LY, EA and moxibustion groups. Moxa cone moxibustion at Shu- and Mu-acupoints of the lung meridian can reduce airway inflammatory reaction and control asthma attacks in asthma mice, which is closely related to its effects in regulating the expressions of RORγt and Foxp3 through PI3K signaling pathway.

The Imbalance in Th17 and Treg Cells in Polycystic Ovarian Syndrome Patients with Autoimmune Thyroiditis

ABSTRACT The ratio of T helper (Th) 17 and T regulatory (Treg) cells in patients with polycystic ovary syndrome complicated with autoimmune thyroiditis (PCOS-AIT) remains unreported. The study aimed to determine the Th17/Treg cell paradigm in PCOS-AIT patients. In peripheral blood mononuclear cells from PCOS patients and controls, the percentages of Th17 and Treg cells were measured by flow cytometry, the mRNA levels of a Th17-related transcription factor (ROR-γt) and a Treg-specific transcription factor (Foxp3) were determined by qRT-PCR, and the levels of Th17-related cytokines and Treg-related cytokines were measured by ELISA. Additionally, to examine the effect of testosterone on the Th17/Treg cell balance in vitro, cultured PCOS-AIT CD4+ T cells were treated with 10 μM testosterone for 24 h, and the Th17/Treg cell proportions and expression of Th17/Treg cell-associated transcription factors and cytokines were analyzed by flow cytometry, qRT-PCR, and ELISA. The Th17 cell percentage, Th17/Treg cell ratio, and expression of Th17-related ROR-γt and IL-17 were significantly higher in peripheral blood mononuclear cells from PCOS-AIT patients than in those from controls. In CD4+ T cells derived from PCOS-AIT patients, testosterone significantly decreased the Th17 cell percentage, Th17/Treg ratio, mRNA level of ROR-γt, and production of Th17-related cytokines and increased the Treg cell percentage, mRNA level of Foxp3, and secretion of Treg-related cytokines. The Th17/Treg cell imbalance favoring proinflammatory Th17 cells is involved in the pathogenesis of PCOS-AIT. Targeting the Th17/Treg cell axis may have therapeutic potential in the treatment of PCOS–AIT.