IgG受体FcγRⅡB调节实验性自身免疫性脑脊髓炎致神经元损伤及Th17/Treg免疫平衡的作用研究  

Role of IgG receptor FcγRⅡB in regulating neuronal damage and Th17/Treg immune balance in experimental autoimmune encephalomyelitis

作　　者：肖林婷 周少珑 周辉 蔡奕秋 陈薇 李鹏 XIAO Linting;ZHOU Shaolong;ZHOU Hui;CAI Yiqiu;CHEN Wei;LI Peng(Department of Neurology,Sanya People's Hospital,Sanya 572000,China;School of Basic Medicine and Life Sciences,Hainan Medical College,Haikou 571199,China)

机构地区：[1]三亚市人民医院神经内科,三亚572000 [2]海南医学院基础医学与生命科学学院,海口571199

出　　处：《中国免疫学杂志》2024年第5期1030-1035,1041,共7页Chinese Journal of Immunology

基　　金：海南省卫生健康行业科研项目(21A200299)。

摘　　要：目的:探究IgG受体FcγRⅡB对实验性自身免疫性脑脊髓炎(EAE)模型小鼠神经元损伤与Th17/Treg失衡的作用。方法:C57BL/6小鼠随机分组为对照组、EAE组、FcγRⅡB组、EAE+FcγRⅡB组,每组15只,皮下注射MOG35-55肽诱导EAE模型,并给予FcγRⅡB慢病毒液处理;造模后每日称量小鼠体质量,进行神经功能评分,持续30 d;30 d后处死小鼠,HE染色观察脑组织病理形态学变化,LFB染色评估脊髓髓鞘结构变化,免疫荧光染色检测脊髓大脑皮质神经元核抗原(NeuN)和Caspase-3表达,TUNEL染色检测神经元细胞凋亡,ELISA检测血清IL-6、IL-17、IL-10及TGF-β水平,流式细胞术分析脾脏Th17、Treg细胞比例分布,Western blot测定脊髓组织维甲酸相关孤儿受体γt(RORγt)与Forkhead家族转录因子3(Foxp3)蛋白表达。结果:与对照组比较,EAE组小鼠体质量下降,神经功能评分升高,脑组织内炎症细胞浸润明显,脊髓中出现脱髓鞘迹象,NeuN荧光表达强度减弱而Caspase-3荧光表达强度增强,TUNEL阳性着色细胞多,细胞凋亡数增加,血清中IL-6和IL-17水平升高,IL-10和TGF-β水平降低,脾脏内Th17细胞比例升高,Treg比例降低,脊髓组织内RORγt蛋白表达上调,Foxp3蛋白表达下调(P<0.05);与EAE组比较,EAE+FcγRⅡB组小鼠体质量增加,神经功能评分降低,脑组织内炎症细胞浸润减轻,脊髓脱髓鞘现象得到改善,NeuN荧光表达强度增强,Caspase-3荧光表达强度减弱,TUNEL阳性着色细胞较少,细胞凋亡数减少,血清中IL-6和IL-17水平降低,而IL-10和TGF-β水平升高,同时脾脏内Th17细胞比例降低,Treg比例升高,脊髓组织内RORγt蛋白表达下调而Foxp3蛋白表达上调(P<0.05)。结论:FcγRⅡB对EAE小鼠具有神经保护作用,可减轻其脑组织炎症细胞浸润及脱髓鞘现象,作用机制可能与调节细胞因子水平及Th17/Treg细胞免疫平衡有关。Objective:To explore effect of IgG receptor FcγRⅡB on neuronal injury and imbalance of Th17/Treg in experimental autoimmune encephalomyelitis(EAE)model mice.Methods:C57BL/6 mice were randomly divided into control group,EAE group,FcγRⅡB group and EAE+FcγRⅡB group,with 15 mice in each group.EAE model was induced by subcutaneous injection of MOG35-55 peptide and treated with FcγRⅡB lentiviral solution.After modeling was established,body weight of mice was weighed every day,and neurological function was scored for 30 d;after 30 days,mice were sacrificed.HE staining was used to observe pathological changes of brain tissue,LFB staining was used to assess structural changes of spinal cord myelin,and immunofluorescence staining was used to detect spinal cord cerebral cortex neuron nuclear antigen(NeuN)and Caspase-3 expressions,TUNEL staining was used to detect apoptosis of neurons,ELISA was used to detect serum IL-6,IL-17,IL-10 and TGF-βlevels,flow cytometry was used to analyze proportion of Th17 and Treg cells in spleen,Western blot was used to determine protein expressions of retinoic acidrelated orphan receptorγt(RORγt)and Forkhead family transcription factor 3(Foxp3)in spinal cord tissue.Results:Compared with control group,mice in EAE group had decreased body weight,increased neurological function scores,obvious infiltration of inflammatory cells in brain tissue,and signs of demyelination in spinal cord,fluorescence expression intensity of NeuN was weakened and fluorescence expression intensity of Caspase-3 was enhanced,there were more TUNEL-positive stained cells,number of apoptotic cells was increased,levels of IL-6 and IL-17 in serum were increased,and levels of IL-10 and TGF-βwere decreased,proportion of Th17 cells in spleen was increased,proportion of Treg was decreased,expression of RORγt protein in spinal cord tissue was up-regulated while relative expression of Foxp3 protein was down-regulated(P<0.05);compared with EAE group,weight of mice in EAE+FcγRⅡB group was increased,neurological fun

关 键 词：实验性自身免疫性脑脊髓炎 FcγRⅡB 神经元损伤 TH17/TREG 免疫 

分 类 号：R744.51[医药卫生—神经病学与精神病学]