Effect of recombinant serine protease from adult stage of Trichinella spiralis on TNBS-induced experimental colitis in mice

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic autoimmune disease. At present, worms and their products has been shown to have protective effects on immune-mediated diseases. Therefore, we aimed to investigate the effect of the recombination Trichinella spiralis (T. spiralis, Ts) adult serine protease-like protein rTs-ADSp-7 on a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD mouse model. Colitis was induced by intrarectal administration of a TNBS solution. The disease activity index (DAI), which included weight loss, diarrhoea, and bloody stool, was measured. Colon segments were stained with haematoxylin and eosin (H.E.) for histopathological score. Cytokine release in the serum was analysed by meso scale discovery (MSD). Cytokine release in the colon was detected by ELISA. Splenocytes were separated, and the cytokine profiles of Th1 (IFN-γ), Th2 (IL-4), Th17 (IL-17A) and Treg cells were analysed by flow cytometry. Our result showed that rTs-ADSp-7 reduced the clinical disease activity of TNBS-induced colitis in mice. In addition, we found that rTs-ADSp-7 reduced the production of Th1- and Th17-related cytokines while upregulating the expression of Th2- and Treg-related cytokines in TNBS-induced colitis mice. rTs-ADSp-7 also increased the population of Th2 and Treg cells in TNBS-induced colitis mice. rTs-ADSp-7 alleviated the severity of TNBS-induced colitis while balancing the CD4⁺ T cell immune response. rTs-ADSp-7 has therapeutic potential for colitis treatment and can be used as a helminth-derived protein therapy for CD or other Th1 immunity-mediated diseases.     

Immunoregulatory Cordyceps sinensis increases regulatory T cells to Th17 cell ratio and delays diabetes in NOD mice

Cordyceps sinensis (CS) is a parasitic fungus, and it has been used widely in traditional Chinese medicines (TCM) for centuries. Many studies have shown that CS has immunoregulatory activity in many disease models, but the underlying mechanism remains elusive. We studied whether CS could suppress the onset of diabetes by altering T lymphocyte subsets in non-obese diabetic (NOD) mice. We found that the onset of type1 diabetes in NOD mice was associated with an imbalance of CD4⁺CD25⁺FoxP3⁺ regulatory T (Treg) cells and IL-17 producing Th17 cells. Oral administration of CS resulted in reduction in the overall incidence of diabetes, and this was due to an increase in the ratio of Treg cells to Th17 in the spleen and pancreatic lymph nodes (PLNs). Taken together, these data imply that CS is able to modulate Treg to Th17 cell ratio in vivo, thus contributing to the inhibition of diabetes.     

Protective effect of isoforskolin in COPD rat model

OBJECTIVE To evaluate effect of Isoforskolin(ISOF) on pulmonary function, T cell and cytokines levels in a chronic obstructive pulmonary disease(COPD) rat model induced by long-term exposure to cigarette smoke(CS). METHODS The experiments were divided into control group, CS model group, roflumilast(0.5 mg·kg-1,ig), ISOF(0.5, 2 mg·kg-1, ig). A rat model of COPD was established by long-term exposure to CS(1 cigarette each rat, once a day for 14 weeks) and the drug was oral y treated with different groups for 14 consecutive weeks.The pulmonary function of rats was measured using the flexi Vent FX4 oscillating animal pulmonary function detector, T cells were analyzed by flow cytometry and the levels of inflammatory cytokines was measured using the Bio-Plex Pro Rat Cytokine Panel. RESULTS ISOF significantly ameliorated pathological damage of lung tissue and improved pulmonary function in COPD rats.Compared with the model group, the pulmonary ventilation function index FEV0.3, FEV0.3/FVC, Cst were significantly increased(P<0.01), and the Crs, G were significantly decreased(P<0.05). ISOF treatment decreased the number of leukocytes and lymphocytes, restored the Th17/Treg balance of T cells and reduced the levels of pro-inflammatory cytokines IL-1β and TNF-α in serum and bronchoalveolar lavage fluid(P<0.05). CONCLUSION ISOF has protective effects in COPD rats by improving lung function, restoring T cell balance and reducing the levels of pro-inflammatory cytokines.     

Airway inflammation and remodeling of cigarette smoking exposure ovalbumin-induced asthma is alleviated by CpG oligodeoxynucleotides via affecting dendritic cell-mediated Th17 polarization

Cigarette smoking (CS) is common in asthma, aggravating inflammatory reactions. However, the current treatment strategies for asthma are still not effective enough, and novel therapeutic approaches are required for CS-induced asthmatic disorders. We here investigated the ability of CpG oligodeoxynucleotides (CpG-ODNs) to inhibit airway inflammation and remodeling in ovalbumin (OVA)-associated asthma in mice exposed to chronic CS, revealing potential mechanistic insights. Lung tissue specimens were histologically analyzed. Th1/Th2/Th17 associated cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung specimens were quantitated by ELISA, qRT-PCR and immunoblot. Parameters of bone marrow-derived dendritic cells (BMDCs) functions were evaluated as well. The results showed that BALB/c mice after CS and OVA treatments developed an asthmatic phenotype with airway inflammation involving both eosinophils and neutrophils, goblet cell metaplasia, airway remodeling, and elevated OVA-specific serum IgE, serum IL-17A, and BALF Th17/Th2 associated cytokines. CpG-ODNs and budesonide were found to synergistically inhibit inflammatory cell recruitment in the lung, airway remodeling, IgE synthesis, and Th17/Th2 associated cytokines. Mechanistically, CpG-ODNs and budesonide acted synergistically on BMDCs via downregulation of TSLP receptor (TSLPR) and IL-23 production, and subsequently contributed to dampen Th17/Th2 polarization in CS-associated asthma. In conclusion, combined administration of CpG-ODNs and budesonide, in a synergistic manner, inhibits airway inflammation, and tissue remodeling mediated by BMDCs by regulating IL-23 secretion and blocking TSLP signaling, which subsequently contribute to alleviate Th17/Th2 imbalance in CS-associated asthma.     

Increased IL-10/IL-17 ratio is aggravated along with the prognosis of patients with chronic lymphocytic leukemia

ObjectiveThis study is to investigate the association between the Treg/Th17 cells and prognosis of chronic lymphocytic leukemia (CLL).MethodsTotally 50 CLL patients and 20 Health controls were included in this study. Regulatory T (Treg) cells and the cell subset secreting IL-17 (Th17) in peripheral blood were detected with flow cytometry. Serum levels of IL-10 and IL-17 were determined with ELISA, and expression of Foxp3 and RORγt was assessed with quantitative real-time PCR.ResultsTreg and Th17 cell proportions in peripheral blood in the CLL patients were significantly higher than control. Serum levels of IL-10 and IL-17, and expression of Foxp3 and RORγt, were significantly increased in the CLL patients. Ratios of Treg/Th17 and IL-10/IL-17 were significantly elevated in the CLL patients. Compared with those before treatment, Treg/Th17 and IL-10/IL-17 ratios were declined in the CLL patients in remission. Compared with the non-remission group, Treg cells were significantly decreased, while Th17 cells were significantly increased, resulting in decreased Treg/Th17 ratio, in the remission group. Moreover, the serum IL-10 level was significantly decreased, while the serum IL-17 level was significantly increased, resulting in declined IL-10/IL-17 ratio, in the remission group. Correlation analysis showed that, Treg and Th17 cell counts were significantly associated with CD38 and ZAP-70 expression in the CLL patients. Moreover, the IL-10/IL-17 ratio was also significantly associated with CLL prognostic factors.ConclusionAltered Treg/Th17 and IL-10/IL-17 ratios in CLL would be aggravated along with the disease progression, which might be used as indicators for the disease prognosis.     

Butyrate inhibit collagen-induced arthritis via Treg/IL-10/Th17 axis

Rheumatoid arthritis (RA) is a chronic autoimmune disorder demanding the development of novel therapeutic strategy. Butyrate is a functional short-chain fatty acid produced by the anaerobic intestinal microbiota. This study aimed to investigate the attenuation of butyrate on RA. The collagen-induced arthritis (CIA) mouse model was established and butyrate was administered in drinking water along with the collagen immunization. The histopathological features, clinical score, paw swelling, as well as the production of pro-inflammatory cytokines including interleukin (IL)-1β, IL-6 and IL-17A were measured to determine the amelioration of butyrate on arthritis. The differentiation of Treg cells and Th17 cells in the splenic cells was assessed by flow cytometry. The expression of Foxp3, IL-10, Rorγt and IL-17A were detected by RT-PCR and FACS immunostaining. Anti-IL10R antibody was used in the CIA and CD4⁺ cell cultures to mediate the effects of butyrate. Butyrate significantly inhibited expressions of IL-1β, IL-6 and IL-17A, but promoted the expression of IL-10. Butyrate also increased systematical Treg cells and reduced Th17 cells. Mechanism study revealed that butyrate directly enhanced the polarization of Treg cells but not Th17 cells. All effects of butyrate on RA were inversed by the co-administered anti-IL10R antibody. This study showed that butyrate administration inhibited arthritis in CIA mice model, suppressed the expression of inflammatory cytokines. The modulation may be mediated the differentiation of CD4 T cells towards Treg cells, which produce anti-inflammatory cytokine IL-10, and thus influenced the function of Th17 cells.     

LL-37对COPD模型大鼠Th17/Treg平衡及炎症反应的调节作用

摘要：目的 观察人源抗菌肽LL-37对慢性阻塞性肺疾病(COPD)大鼠辅助性T细胞17(Th17)/调节性T细胞(Treg)平衡、炎症 反应的影响,并探讨可能机制。方法 40只Wistar大鼠随机分为正常组、COPD组、LL-37组、LL-37联合DAPT(Notch1/Jagged1 信号通路抑制剂)组。正常组室温下正常喂养,COPD组、LL-37组、LL-37联合DAPT组采用烟熏法建立COPD模型。LL-37组大 鼠经鼻滴入LL-37(10 μg) 50 μL,LL-37联合DAPT组大鼠经鼻滴入总体积50 μL的LL-37(10 μg)+DAPT(10 μg)。正常组、COPD 组大鼠分别经鼻滴入等体积的生理盐水。检测外周血Th17、Treg细胞占比;检测肺泡灌洗液(BALF)中白介素-8(IL-8)、白三烯 B4(LTB4)含量;HE染色检测气道重塑指标;Western Blot法检测肺组织Notch1、Jagged1、发状分裂相关增强子1(Hes1)蛋白表 达量。结果 与COPD组比较,LL-37组外周血Th17占比和Th17/Treg、BALF中IL-8、LTB4含量、管壁厚度/外径(MT%)及管壁 面积/气管总面积(MA%)均降低,Treg占比升高(P＜0.05);与LL-37组比较,LL-37联合DAPT组外周血Th17占比和Th17/Treg、 BALF中IL-8、LTB4含量、MT%及MA%均升高,Treg占比降低(P＜0.05)。与COPD组比较,LL-37组Notch1、Jagged1、Hes1蛋 白表达量升高(P＜0.05);与LL-37组比较,LL-37联合DAPT组Notch1、Jagged1、Hes1蛋白表达量降低(P＜0.05)。结论 人源抗 菌肽LL-37可调节COPD大鼠外周血Th17/Treg失衡,抑制炎症反应及气道重塑,激活Notch1/Jagged1信号通路可能是其发挥治疗 作用的机制之一。     

LAT alleviates Th2/Treg imbalance in an OVA-induced allergic asthma mouse model through LAT-PLC-γ1 interaction

IntroductionLow expression of linker for activation of T cells (LAT) is observed in asthma. LAT and its downstream regulator, phospholipase C-gamma 1 (PLC-γ1) play important roles in the T cell antigen receptor signaling pathway, and their interaction is associated with CD4⁺ cell polarization. Here, we investigated whether LAT can alleviate the imbalance among CD4⁺ cell subgroups and the possible mechanism.MethodsAn ovalbumin-induced allergic asthma mouse model was established and LAT plasmid was delivered. The pathological changes in lung were evaluated by hematoxylin and eosin and periodic acid-Schiff staining. The typical cytokines released by T helper 2 (Th2) and regulatory T (Treg) cells were measured using enzyme-linked immunosorbent assay and the number of Th1, Th2, and Treg cells were determined using flow cytometry. Lung CD4⁺ T cells were isolated by magnetic isolation. The mRNA expression of LAT and PLC-γ1 was determined by real-time PCR. Co-Immunoprecipitation was performed to confirm the interaction between LAT and PLC-γ1. The protein expression of LAT, PLC-γ1 and corresponding downstream signaling factors were determined by western blotting.ResultsThe delivery of LAT DNA to the lung could suppress an overactive Th2 response by decreasing allergic response and Th2 cytokine secretion, and by increasing Treg cytokine secretion. The Th2/Treg imbalance in lung and decreased phosphorylated PLC-γ1 expression in lung CD4⁺ T cells were rectified by LAT DNA delivery. Excessive activation of the Raf-MEK-ERK and PI3K-AKT-CREB pathways after asthma is attenuated by LAT.ConclusionThe site-specific delivery of LAT DNA to the lung could suppress an overactive Th2 response and rectify the Th2/Treg imbalance in asthmatic mouse model. LAT-PLC-γ1 interaction may contribute to LAT activity in vivo and LAT protects against asthma partly via Raf-MEK-ERK and PI3K-AKT-CREB pathways. The delivery of LAT DNA could offer a novel and safe strategy for asthma prevention.     

3, 3′-diindolylmethane alleviates steatosis and the progression of NASH partly through shifting the imbalance of Treg/Th17 cells to Treg dominance

This study was designed to discuss the effects of 3, 3′-diindolylmethane (DIM) on methionine–choline-deficient (MCD)-diet induced mouse nonalcoholic steatohepatitis (NASH) and the potential mechanisms. NASH mice were administrated with or without DIM at different concentrations for 8 weeks. Both the in-vivo and in-vitro effects of DIM on Treg/Th17 imbalance during NASH progression were analyzed. The in-vivo blocking of CD25 or IL-17 was performed to respectively deplete respective function of Treg or Th17 subset. Besides, with the assistance of AhR antagonist CH223191 and anti-TLR4 neutralizing antibody, we designed the in-vitro DIM-incubation experiments to discuss the roles of aryl hydrocarbon receptor (AhR) (CYP1A1, CYP1B1) and toll-like receptor 4 (TLR4) on DIM's effects when shifting Treg/Th17 imbalance. Notably, in NASH mouse models, DIM alleviated hepatic steatosis and inflammation, and shifted the Treg/Th17 imbalance from MCD diet-induced Th17 dominance to Treg dominance. In-vitro, DIM not only significantly up-regulated the mRNAs of Foxp3 (Treg-specific) in purified spleen CD4⁺ T cells, but also enhanced the immunosuppressive function of these Treg cells. Besides, DIM significantly up-regulated the proteins of CYP1A1 and CYP1B1 whereas down-regulated those of TLR4 on CD4⁺ T cells from MCD-diet mice. Moreover, blocking AhR attenuated while blocking TLR4 enhanced the effects of DIM when regulating Treg/Th17 imbalance. Conclusively, DIM could be used as a potential therapeutic candidate to treat NASH based on its dramatic induction of Treg dominance to alleviate intra-hepatic inflammation, suggesting us a clue that the dietary cruciferous vegetables (containing abundant DIM) might exist as a protective factor for patients with NASH-related liver diseases.     

Are Th17 cells and their cytokines a therapeutic target in Guillain–Barré syndrome?

Introduction: Guillain–Barré syndrome (GBS) is an immune-mediated inflammatory disorder of the peripheral nervous system (PNS). Experimental autoimmune neuritis (EAN) is a useful animal model for studying GBS. Currently, GBS remains a life-threatening disorder and more effective therapeutic strategies are in urgent need.

Areas covered: Accumulating evidence has revealed that T helper (Th) 17 cells and their cytokines are pathogenic in GBS/EAN. Drugs attenuated clinical signs of GBS/EAN, in part, by decreasing Th17 cells or IL-17A. Th17 cells and their cytokines might be potential therapeutic targets. Approaches targeting Th17 cells or their cytokines are in development in treating Th17 cells-involved disorders. In this review, we summarize the up-to-date knowledge on roles of Th17 cells and their cytokines in GBS/EAN, as well potential approaches targeting Th17 cells and their cytokines as clinical applications.

Expert opinion: As Th17 cells produce different sets of pro-inflammatory cytokines and Th17-related cytokines are not exclusively produced by Th17 cells, targeting Th17 cell development may be superior to blocking a single Th17 cytokine to treat Th17 cells-involved disorders. Considering the essential role of retinoic acid-related orphan receptor γT (RORγT) and IL-23 in Th17 cell development, RORγT inhibitors or IL-23 antagonists may provide better clinical efficacy in treating GBS/EAN.     

CNI induced Th17/Treg imbalance and susceptibility to renal dysfunction in renal transplantation

Calcineurin inhibitors (CNI) prevent graft rejection by blocking interleukin-2 (IL-2), which was required for development and function of Foxp3⁺CD4⁺CD25⁺ regulatory T cells (Treg). Recently, IL-2 was reported to play a part in the inhibition of Th17 cells. The renal transplantation recipient who used CNI regularly might have Th17/Treg imbalance with increased Th17 cells and decreased Treg cells, which would cause renal dysfunction even rejection. To assess the effect of CNI on Th17 cells and Treg cells, we included 123 renal transplantation recipients (101 in a stable stage and 22 with renal dysfunction) and 27 healthy volunteers. Among all the recipients, 103 recipients used CNI and 20 recipients used sirolimus without CNI. The recipients who used CNI were further classified into four groups according to the blood levels of CNI: Of all these subjects, Th17 and Treg frequencies in the peripheral blood were analyzed by flow cytometry (FCM). Serums IL-17, IL-23, IL-6, IFN-r, and TGF-β were analyzed by ELISA. The results demonstrated that the transplantation recipient treated by CNI revealed an obvious increase in peripheral Th17 frequencies and a significant decrease in Treg frequencies when compared with the sirolimus group and healthy people (P < 0.05). Even more, the transplantation recipient with renal dysfunction had the highest level of Th17 cells (P < 0.05) while the lowest Treg cells compared with stable recipient and healthy control, with increased serums IL-6 and IL-17. Our results indicated that CNI was associated with Th17/Treg imbalance in peripheral blood, which supported the followed generation of renal dysfunction after transplantation.     

Th17/Treg平衡在类风湿关节炎中作用的研究进展

类风湿性关节炎(rheumatoid arthritis,RA)是一种以慢性多关节滑膜炎为主要特征的自身免疫性疾病。虽然目前对于RA的确切发病机制尚不明确,但一般认为和T细胞相关。最近研究发现调节性T细胞(regulatory T cell,Treg)和Th17细胞在RA的发生发展中发挥重要作用。Th17细胞能够分泌促炎症因子IL-17,通过诱导基质金属蛋白酶(ma-trix metallo proteinases,MMPs)和破骨细胞生成,促进骨滑膜炎症、骨和关节损伤;而Treg则通过释放抑制性细胞因子IL-10和TGF-β发挥免疫效应,调控RA中的炎症性免疫应答过程。单独TGF-β作用下诱导初始T细胞分化为Treg,而在TGF-β和IL-6共同作用下诱导初始T细胞分化为Th17细胞,因此,Th17和Treg细胞在特定的细胞因子微环境下可以相互转化。调节Th17/Treg之间的平衡可能成为治疗RA的新方法。该文将对Th17/Treg平衡在RA发生发展中的调节作用作一综述。     

Interleukin-22 exacerbates airway inflammation induced by short-term exposure to cigarette smoke in mice

Aim:

Interleukin-22 (IL-22) exhibits both proinflammatory and anti-inflammatory properties in various biological processes. In this study we explored the effects of exogenous recombinant IL-22 (rIL-22) on cigarette smoke (CS)-induced airway inflammation in mice.

Methods:

Male C57BL/6 mice were divided into groups: (1) CS group exposed to tobacco smoke for 3 consecutive days, (2) rIL-22 group received rIL-22 (100 mg/kg, ip), and (3) CS plus rIL-22 group, received rIL-22 (100 mg/kg, ip) before the CS exposure. The airway resistance (Rn), lung morphology, inflammatory cells in the airways, and inflammatory cytokines and CXCR3 ligands in both bronchoalveolar lavage (BAL) fluids and lung tissues were analyzed.

Results:

CS alone significantly elevated IL-22 level in the BAL fluid. Both CS and rIL-22 significantly augmented airway resistance, an influx of inflammatory cells into the airways and lung parenchyma, and significantly elevated levels of pro-inflammatory cytokines (TGFβ1 and IL-17A) and CXCR3 chemokines (particularly CXCL10) at the mRNA and/or protein levels. Furthermore, the effects of rIL-22 on airway resistance and inflammation were synergistic with those of CS, as demonstrated by a further increased Rn value, infiltration of greater numbers of inflammatory cells into the lung, higher levels of inflammatory cytokines and chemokines, and more severe pathological changes in CS plus rIL-22 group as compared to those in CS group.

Conclusion:

Exogenous rIL-22 exacerbates the airway inflammatory responses to CS exposure in part by inducing expression of several proinflammatory cytokines and CXCR3 ligands.