Activation of β2-adrenergic Receptor Alleviates Collagen-induced Arthritis by Ameliorating Th17/Treg Imbalance

Background: Recent research in our laboratory shows that CD4+ T cells express the β2 adrenergic receptor (β2-AR), and the sympathetic neurotransmitter norepinephrine regulates the function of T cells via β2-AR signaling. However, the immunoregulatory effect of β2-AR and its related mechanisms on rheumatoid arthritis is unknown.Objective: To explore the effects of β2-AR in collagen-induced arthritis (CIA) on the imbalance of T helper (Th) 17/ regulatory T (Treg) cells.Methods: In DBA1/J mice, collagen type II was injected intradermally at the tail base to prepare the CIA model. The specific β2-AR agonist, terbutaline (TBL), was administered intraperitoneally beginning on day 31 and continuing until day 47 after primary vaccination, twice a day. Magnetic beads were used to sort CD3+ T cells subsets from spleen tissues.Results: In vivo, β2-AR agonist TBL alleviated arthritis symptoms in the CIA mice including histopathology of the ankle joints, four limbs’ arthritis score, the thickness of ankle joints, and rear paws. After TBL treatment, in the ankle joints, the levels of proinflammatory factors (IL-17/22) notably decreased and the levels of immunosuppressive factors (IL-10/TGF-β) significantly increased. In vitro, ROR-γt protein expression, Th17 cell number, mRNA expression and the releasing of IL-17/22 from CD3+ T cells reduced following TBL administration. Moreover, TBL enhanced the anti-inflammatory responses of Treg cells.Conclusion: These results suggest that β2-AR activation exerts anti-inflammatory effects through the amelioration of Th17/Treg imbalance in the CIA disease.     

GATA3 up-regulation associated with surface expression of CD294/CRTH2: a unique feature of human Th cells

GATA-3 and T-box expressed in T cells (T-bet) play central roles in Th-cell development and function. Consistently, studies in mice document their selective expression in Th1 and Th2 cells, respectively. In contrast, it is not clear whether these genes are regulated in human Th cells. Here we show that T-bet expression is polarized to a comparable degree in human and mouse Th-cell cultures, while only mouse GATA3 is subject to substantial regulation. This did not reflect differential skewing efficiency in human versus mouse cultures, as these contained similar frequencies of IFN-gamma- and IL-4-producing cells. However, GATA-3 was expressed at significantly higher levels in human IL-4-producing cells enriched via capture with monoclonal antibodies (mAbs) against the PGD(2) receptor, CRTH2, the best selective Th2-cell surface marker to date. Along with increased IL-4 and GATA-3, CRTH2(+) Th cells isolated from Th2-skewed cultures or the circulating memory pool exhibited markedly decreased IFN-gamma and T-bet expression. Thus, the human GATA-3 gene is not regulated in response to polarizing signals that are sufficient to direct Th2-specific expression in mouse cells. This postulates the involvement of an additional level of complexity in the regulation of human GATA-3 expression and stresses the existence of nontrivial differences in the regulation of human versus mouse T-cell function.     

The effect of synthetic retinoid,Am80, on T helper cell development and antibody production in murine collagen-induced arthritis

Abstract

Retinoids are known to promote T helper (Th)2 and regulatory T cell (Treg) differentiation, and suppress Th1 and Th17 in vitro. Am80, a synthetic retinoid, is reported to ameliorate collagen-induced arthritis (CIA). The aims of this study are to determine the effects of Am80 on CIA in detail, and on Th development and antibody (Ab) production in vivo. Murine CIA was induced by immunization with bovine type II collagen (CII) at days 1 and 22. Treatment with Am80 from day 1 to 35 significantly lowered clinical arthritis score, suppressed cellular infiltration and bone destruction in the joint, decreased interleukin (IL)-17 and increased interferon (IFN)-γ production by CII-stimulated splenocytes, and decreased proportion of Foxp3⁺ splenic CD4 T cells and serum anti-CII Ab levels. Thus, Am80 inhibited Th17 and Treg and enhanced Th1 differentiation in vivo. In contrast, Am80 applied from day 15 to 35 did not alter arthritis score, IL-17 or IFN-γ production by CII-stimulated splenocytes, but decreased the proportion of Foxp3⁺ splenic CD4 T cells and serum anti-CII Ab levels. Am80 exhibits inhibitory effects on CIA and might regulate both Th development and Ab production in vivo. Decreased Th17 by treatment with Am80 might be responsible for the attenuation of arthritis.     

小剂量白细胞介素-18联合白细胞介素-10在早期Ⅱ型胶原诱导性关节炎中的作用研究

目的 研究不同细胞因子微环境下,白细胞介素(IL)-18对早期Ⅱ型胶原诱导性关节炎(CIA)的作用.方法 CIA小鼠,发病前给予每只重组小鼠腹腔注射IL-18(0.2 μg/d)/IL-10(0.1 μg/d),IL-18(0.2 μg/d)IL-4(0.1 μg/d),IL-18(0.2 μg/d)IL-12(0.1 μg/d),连用5 d,用关节炎评分评估关节炎病情的进展,用反转录聚合酶链反虚(RT-PCR)测定CIA小鼠髌骨及邻近滑膜组织的细胞因子表达水平;用组织学染色评价膝关节的软骨和骨破坏.采用Wilcoxon rank检验. 结果 IL-18/IL-4组关节炎评分轻度降低.IL-18/IL-10联合治疗有效抑制了C1A小鼠的关节炎症反应,免疫第38天治疗组关节炎评分(0.12±0.20)显著低于对照组(0.29±0.19,P<0.05),阻止了滑膜部位的炎细胞浸润,防止了软骨的破坏.滑膜和其附近软骨的Th1型细胞因子[IL-18(0.22±0.06),IL-12(0.14±0.05)]与炎症性细胞因子[IL-6(0.22±0.11)]水平与对照组相比显著降低(P<0.05),Th2型细胞因子[IL-10(6.35±0.12),IL-4(3.57±0.13)]水平与对照组相比明显升高(P<05). IL-18R(0.40±0.15)水平明显降低(P<0.05).T-bet水平降低,转录因子(GATA)-3水平(5.7l±0.11)显著升高(P<0.05).结论 IL-18/IL-10免疫干预尚未发病的CIA小鼠,可以抑制Th1型免疫反应,使免疫反应向Th2逆转,其机制可能为下调了IL-18/IL-18R水平,诱导了转录因子GATA-3的表达.     

华支睾吸虫成虫抗原和排泄分泌产物对T细胞的作用研究

目的观察华支睾吸虫成虫抗原(Crude antigen,CA)、排泄/分泌产物(excretory-secretory products,ESPs)对T细胞的作用。方法体外分离小鼠骨髓细胞诱导分化为未成熟骨髓树突状细胞(immature DC,iDC);磁珠分选仪分选小鼠脾脏细胞的初始CD4+T细胞;流式细胞术检测DC、CD4+T细胞的纯度;抗原刺激DC细胞,实验分为PBS阴性对照组,LPS阳性对照组,CA和ESPs刺激组;负载抗原后的DC细胞与分选的CD4+T细胞共培养72h;Real time-PCR检测T-bet、GATA3mRNA的相对表达量;ELISA检测细胞培养上清中IFN-γ、IL-4细胞因子的表达量。结果与PBS组相比,ESPs刺激组Tbet、GATA3mRNA表达水平升高(P0.05),而CA刺激组T-bet、GATA3 mRNA表达水平差异不显著;与PBS组相比,ESPs刺激组细胞因子IFN-γ、IL-4的含量均升高(P0.05),CA刺激组仅IFN-γ的分泌增高(P0.05),IL-4无明显变化。结论 CA可能诱导宿主产生Th1型免疫应答,ESPs可能诱导宿主产生Th1型、Th2型免疫应答。     

Impaired IL-4 and c-Maf expression and enhanced Th1-cell development in Vav1-deficient mice

Although c-Maf is crucial for Th2 differentiation and production of interleukin 4 (IL-4), its regulation is poorly understood. We report that Vav1-/- CD4+ T cells display deficient T-cell receptor (TCR)/CD28-induced IL-4 and c-Maf expression and, conversely, enhanced interferon gamma (IFN-gamma) production and T-bet expression (even when cultured under Th2-polarizing conditions), but intact expression of other Th2 cytokines and GATA-3. Up-regulation of c-Maf was dependent on Ca2+/nuclear factor of activated T cell (NFAT) and, together with IL-4 production, could be rescued in Vav1-/- T cells by Ca2+ ionophore. Deficient IL-4 production was restored by retrovirus-mediated Vav1 expression, but only partially by retroviral c-Maf expression. Similar IL-4 --> IFN-gamma skewing was observed in intact, antigen-primed Vav1-/- mice. Thus, Vav1 is selectively required for IL-4 and c-Maf expression, a requirement reflecting, at least in part, the dependence of c-Maf expression on Ca2+/NFAT signaling.     

白藜芦醇对JurcatT细胞分化为Th1/Th2细胞作用的影响及机制

目的探讨白藜芦醇调节Jurkat T细胞分泌为Th1/Th2型细胞作用的影响。方法将不同浓度的白藜芦醇作用于受植物血凝素（PHA）刺激的Jurkat T细胞,于不同时间点分别用ELISA法检测Th1型细胞因子IFN-γ和Th2型细胞因子IL-10;RT-PCR法检测T-bet和GATA-3 mRNA表达。结果白藜芦醇作用后IFN-γ、IL-10及T-bet mRNA、GATA-3 mRNA的表达均明显降低,具有浓度和时间依赖性。结论白藜芦醇对受PHA刺激的JurcatT细胞由Th0向Th1、Th2细胞分化起抑制作用。     

IL-32 aggravates synovial inflammation and bone destruction and increases synovial natural killer cells in experimental arthritis models

This study was performed to investigate the effects of IL-32 on joint inflammation, bone destruction, and synovial cytokine expressions, and on synovial natural killer (NK) cell expressions in collagen-induced arthritis (CIA). CIA was induced by type II collagen in DBA1 mice, and phosphate-buffered saline (PBS group) or IL-32 (IL-32 group) were injected into both knee joints at day 28 and 32, then mice were killed at day 35. Severity of synovial inflammation and bone destruction was determined by histological scoring method, and synovial cytokine expressions such as IL-1β, TNF-α, IL-17, IL-18, IFN-γ, IL-21, and IL-23 were measured by real-time RT-PCR and western blot. Synovial NK cell expressions were determined by real-time RT-PCR, western blot and immunohistochemistry, and chemokines and chemokine receptors expressions that are associated with NK cell migration were determined by real-time RT-PCR. Scores of synovial inflammation and bone destruction, synovial expressions of IL-1β, TNF-α, IL-18, and IFN-γ were significantly increased in IL-32 group compared with PBS group. Synovial expressions of NK cell, and chemokines (CCL2 and CXCL9) and chemokine receptors (CCR2 and CCR5) that are associated with NK cell migration were significantly increased in IL-32 group compared with PBS group. IL-32 aggravated joint inflammation and bone destruction and increased synovial expressions of inflammatory cytokine and NK cells in CIA. These results suggest that IL-32 play a role in joint inflammation and bone destruction, and IL-32 might be a new target for treatment of rheumatoid arthritis.     

补脾益气方药对哮喘大鼠Th1/Th2失衡的调节及机制

目的观察补脾益气方药对哮喘大鼠Th1/Th2失衡的免疫调节作用及机制。方法 SPF级雄性Wistar大鼠随机分为对照组、哮喘组、生理盐水治疗组、地塞米松组、补脾益气方药治疗组。检测支气管肺泡灌洗液(BALF)中嗜酸性细胞、巨噬细胞、淋巴细胞和中性粒细胞比例;采用ELASA方法检测BALF中IL-4和IFN-γ的含量;采用Western blot方法检测肺组织GATA-3和T-bet的表达。结果模型组和生理盐水治疗组与正常组比较,BALF中嗜酸性粒细胞、淋巴细胞和中性粒细胞的比例及IL-4含量均明显升高,IFN-γ含量显著下降;GATA-3表达增高,T-bet表达降低。经补脾益气方药与地塞米松治疗后,BALF中嗜酸性粒细胞、淋巴细胞和中性粒细胞的比例和IL-4含量均明显下降,IFN-γ含量显著升高;GATA-3表达下调,T-bet表达上调。上述结果均差异显著,具有统计学意义(P<0.01)。结论补脾益气方药对Th1/Th2失衡有调节作用,这种作用是通过调节GATA-3和T-bet的协调表达来实现。     

Effect of Cytomegalovirus Recombinant Phosphoprotein 150 (pp150) on Function and Maturation of Murine Dendritic Cells: an In-Vitro Study

Background: Tegument protein pp150 of cytomegaloviruses (CMVs) plays a vital role in all stages of viral life cycle, representing the most important tegument protein candidate for HCMV treatment. However, the exact role of pp150 in immune regulation is yet to be elucidated. Objective: To examine the effects of pp150 on the maturity and function of murine dendritic cells (DCs). Methods: Maturity status (CD40, CD86, and MHC-II expression) and phagocytic capacity of DCs (dextran uptake assay) were characterized. Gene expression profiles of ROR-γ, GATA-3, T-bet, and FOXP-3 as well as the protein expression of INF-γ (Th1), IL-4 (Th2), IL-35 (Treg), IL-17A (Th17), IL-22, TNF-α, IL-6, and IL-2 were evaluated in T cells co-cultured with DCs. Results: A significant increase in CD40, CD86, and CCR7 expression and a reduction in the phagocytosis rate were observed in pp150-stimulated DCs compared with unstimulated DCs. T cells co-cultured with stimulated DCs showed higher expressions of ROR-γ, IL-6, IL-2, IL-17A, IL-22, and TNF-α. Conclusion: Despite improvements in maturity status, pp150-stimulated DCs does not seem to be able to induce Th1 or Th2 immunity. In fact, Th17 and its mediators, IL-17A and IL-22, might be the main inflammatory factors involved in pp150-stimulated DC's action mechanism. However, it is necessary to conduct further investigations to corroborate these observations.