The interaction of dendritic cells and γδ T cells promotes the activation of γδ T cells in experimental autoimmune uveitis

Uveitis is a severe inflammatory disease that can cause visual impairment.Recently,activatedγδT cells were proved to play a central role in the development of experimental autoimmune uveitis(EAU).However,the mechanism underlyingγδT cell activation in EAU is incompletely known.In this study,we determined the percentage changes in and the phenotypes ofγδT cells and dendritic cells(DCs)obtained from the spleens of immunized C57BL/6(B6)mice,an animal model of EAU.We found that the number ofγδT cells and DCs obviously increased during the inflammation phase of EAU(days 16-20 of our experiment),and that during this time,γδT cells expressed high levels of CD69 and the integrin lymphocyte function-associated antigen-1(LF A-1)and secreted high levels of interleukin(IL)-17A.Moreover,DCs obtained during this phase expressed high levels of CD80,CD83,CD86,and intracellular cell adhesion molecule-1(ICAM-1).Furthermore,we studied the interaction between DCs andγδT cells by using flow cytometry and confocal microscopy in order to determine whether DCs affectedγδT-cell activation in vitro.Co-cultures of the two types of cells showed that DCs induced high levels of CD69,LFA-1,and I-17A inγδT cells.Imaging studies revealed contact between the DCs andγδT cells.This interaction was mediated by the accumulation of ICAM-1 and LFA-1 at the interface of DCs-γδT cells.Thus,the activation ofγδT cells in EAU was promoted by DCs interacting withγδT cells.

Rapamycin ameliorates experimental autoimmune uveoretinitis by inhibiting Th1/Th2/Th17 cells and upregulating CD4+CD25+ Foxp3 regulatory T cells

· AIM: To determine the effects of rapamycin on experimental autoimmune uveoretinitis(EAU) and investigate of role of rapamycin on T cell subsets in the disease.·METHODS: EAU was induced in rats using peptides1169 to 1191 of the interphotoreceptor binding protein(IRBP). Rapamycin(0.2 mg/kg/d) was administrated by intraperitoneal injection for a consecutive 7d after immunization. Th1/Th2/Th17 cytokines, TGF-β1, and IL-6produced by lymphocyteswere measured by ELISA, while Th17 cells and CD4 +CD25 + regulatory T cells(Tregs)from rat spleen were detected by flow cytometry.·RESULTS: Intraperitoneal treatment immediately after immunization dramatically ameliorated the clinical course of EAU. Clinical responses were associated with reduced retinal inflammatory cell infiltration and tissue destruction. Rapamycin induced suppression of Th1/Th2/Th17 cytokines, including IFN-γ, IL-2, IL-17, IL-4, and IL-10 release from T lymphocytes of EAU rats, in vitro.Rapamycin also significantly increased TGF-β1production but had no effect on IL-6 productionof T lymphocytes from EAU rats in vitro. Furthermore,rapamycin decreased the ratio of Th17 cells/CD4 +T cells and upregulated Tregs in EAU, as detected by flow cytometry.·CONCLUSION: Rapamycin effectively interferes with T cell mediated autoimmune uveitis by inhibiting antigen-specific T cell functions and enhancing Tregs in EAU.Rapamycin is a promising new alternative as an adjunct corticosteroid-sparing agent for treating uveitis.

β-arrestin1在实验性自身免疫性葡萄膜炎中的表达

目的:初步探讨β-arrestin1在实验性自身免疫性葡萄膜炎(experimental autoimmune uveitis,EAU)中的表达。方法:成功建立EAU动物模型后,通过免疫组织化学和RT-PCR的方法检测β-arrestin1在EAU小鼠脾脏细胞中的表达。结果:免疫组织化学和RT-PCR均提示β-arrestin1在EAU小鼠脾脏细胞中的表达较正常小鼠增高。结论:β-arrestin1可能在EAU的发生发展中起着重要作用。

雷公藤红素在实验性自身免疫性葡萄膜炎(EAU)小鼠眼组织中的抗炎作用及其对小胶质细胞极化的影响

目的探讨雷公藤红素在实验性自身免疫性葡萄膜炎(EAU)小鼠眼组织中的抗炎作用及其对小胶质细胞极化的影响。方法取健康6~8周龄B10.RIII小鼠36只,随机分为正常对照组、EAU溶剂对照组、雷公藤红素干预组,每组12只。将光感受器间维生素A类结合蛋白161-180和完全弗氏佐剂充分乳化混合后,注射于EAU溶剂对照组和雷公藤红素干预组小鼠双侧大腿和尾部皮下,总体积200μL,每只小鼠注射光感受器间维生素A类结合蛋白161-180的量为50μg。免疫后第7-14天,雷公藤红素干预组小鼠每天接受0.5 mg·kg^(-1)雷公藤红素腹腔注射治疗,EAU溶剂对照组小鼠注射同等剂量的无菌PBS缓冲溶液。免疫后第14天,通过裂隙灯显微镜观察各组小鼠眼前节表现及行组织切片HE染色,并参照Caspi分级标准对各组小鼠进行临床评分及组织病理学评分;免疫荧光染色观察小鼠眼内小胶质细胞活化情况;Western blot检测小鼠视网膜中诱导型一氧化氮合酶(iNOS)、精氨酸酶-1(Arg1)蛋白表达水平;qRT-PCR检测小鼠视网膜中炎症因子肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1β、IL-6 mRNA相对表达量。采用Graphpad Prism 9.0统计软件进行数据分析。结果免疫后第14天,通过裂隙灯显微镜观察发现,EAU溶剂对照组小鼠眼前节可见虹膜血管扩张充血明显、角膜水肿、前房渗出;而雷公藤红素干预组小鼠眼前节炎症明显减轻,可见虹膜血管轻度充血。与正常对照组相比,EAU溶剂对照组与雷公藤红素干预组小鼠临床评分均升高,差异均有统计学意义(均为P<0.05)。雷公藤红素干预组小鼠临床评分低于EAU溶剂对照组,差异有统计学意义(P<0.05)。HE染色结果显示,免疫后第14天,EAU溶剂对照组小鼠出现严重的视网膜皱褶和脱离,炎症细胞弥漫浸润;而雷公藤红素干预组小鼠视网膜结构破坏轻微,可见少量炎症细胞浸润。与正常对照组相比,EAU溶剂对照组与雷公藤红素干预组小鼠组织病理学评分均升高,差异均有统计学意义(均为P<0.05)。雷公藤红素干预组小鼠组织病理学评分低于EAU溶剂对照组,差异有统计学意义(P<0.05)。正常对照组、EAU溶剂对照组、雷公藤红素干预组小鼠眼内Iba1+细胞密度分别为(1.00±0.12)%、(36.07±4.57)%、(1.83±0.36)%,与正常对照组相比,EAU溶剂对照组及雷公藤红素干预组小鼠眼内Iba1+细胞数增加,差异均有统计学意义(均为P<0.05);与EAU溶剂对照组相比,雷公藤红素干预组小鼠眼内Iba1+细胞数明显减少,差异有统计学意义(P<0.05)。与正常对照组相比,EAU溶剂对照组小鼠视网膜中iNOS、Arg1蛋白表达水平均升高,差异均有统计学意义(均为P<0.01);与EAU溶剂对照组相比,雷公藤红素干预组小鼠视网膜中iNOS蛋白表达水平降低,差异有统计学意义(P<0.01)。与正常对照组相比,EAU溶剂对照组小鼠视网膜中TNF-α、IL-1β、IL-6 mRNA相对表达量均升高,差异均有统计学意义(均为P<0.05);与EAU溶剂对照组相比,雷公藤红素干预组小鼠视网膜中TNF-α、IL-1β、IL-6 mRNA相对表达量均下降,差异均有统计学意义(均为P<0.05)。结论雷公藤红素可抑制M1型小胶质细胞活化,减少EAU小鼠视网膜炎症因子TNF-α、IL-1β、IL-6的产生,减轻炎症反应。