过刊浏览

IgG型浆细胞在溃疡性结肠炎小鼠蛋白C系统变化中的作用

林旭红, 郭俊玲, 温玉清, 李玉霞, 魏丹丹, 杨瑞林, 穆小云, 王慧超

河南大学淮河医院检验科，转化医学中心，开封 475000；河南大学淮河医院心内科；甲状腺乳腺外科，河南大学医学院，开封 475000；河南大学第一附属医院肾内科，开封 475000

摘要

本文旨在探讨IgG型浆细胞在溃疡性结肠炎(ulcerative colitis, UC)小鼠蛋白C系统(protein C system, PCS)变化中的作用。利用4%硫酸葡聚糖钠(dextran sulfate sodium, DSS)模拟小鼠UC，免疫荧光法观察结肠组织黏膜固有层浆细胞及免疫复合物IgA/M/G的类型，分离小鼠结肠组织黏膜固有层细胞，用抗CD38+、CD54+抗体双标、流式细胞术检测浆细胞数量，以抗IgA/M/G抗体标记，流式细胞术检测浆细胞类型；模拟IgG型免疫复合物刺激分离培养的巨噬细胞，ELISA法检测上清中促炎细胞因子TNF-α和IL-6的变化；流式细胞术检测TNF-α、IL-6对结肠黏膜微血管内皮细胞蛋白C受体(endothelial protein C receptor, EPCR)、血栓调节蛋白(thrombomodulin, TM)表达的影响，发色底物法检测TNF-α、IL-6对微血管内皮细胞激活的蛋白C (activated protein C, APC)活性的影响。结果显示：与对照组相比，DSS组小鼠结肠组织大量IgG型浆细胞浸润(P < 0.05)，黏膜固有层IgG型免疫复合物水平显著升高；分离培养的巨噬细胞与模拟IgG型免疫复合物共孵育后，上清中炎性细胞因子TNF-α和IL-6明显增高(P < 0.01)；同时TNF-α或IL-6与小鼠结肠黏膜微血管内皮细胞共孵育后，内皮细胞表达EPCR、TM的能力均有所降低(P < 0.05或P < 0.01)，其APC活性明显降低(P < 0.05或P < 0.01)。以上结果提示，UC时IgG型浆细胞数量增加，并通过形成免疫复合物，从而影响巨噬细胞分泌促炎细胞因子，进而影响血管内皮细胞功能，抑制PCS。浆细胞有望成为治疗UC的新靶点。

关键词： 浆细胞; 溃疡性结肠炎 ; 免疫复合物 ; 巨噬细胞 ; 蛋白C系统

分类号：R363.2

Role of IgG plasma cells in the change of protein C system in ulcerative colitis

LIN Xu-Hong, GUO Jun-Ling, WEN Yu-Qing, LI Yu-Xia, WEI Dan-Dan, YANG Rui-Lin, MU Xiao-Yun, WANG Hui-Chao

Department of Clinical Laboratory, Translational Medicine Center, Huaihe Hospital Affiliated to Henan University, Kaifeng 475000, China； Department of Clinical Cardiology； Department of Thyroid Breast Surgery, Huaihe Hospital Affiliated to Henan University, Medical Sciences of Henan University, Kaifeng 475000, China； Department of Nephrology, First Affiliated Hospital of Henan University, Kaifeng 475000, China

Abstract

The present study is designed to explore the role of plasma cells in the change of protein C system (PCS) in ulcerative colitis (UC). Dextran sulfate sodium (DSS, 4% in concentration) was used to induce mouse UC model. The plasma cells and the type of immune complex in colon were observed by immunofluorescence. The amount and type of plasma cells separated from colonic mucosal lamina propria were detected by flow cytometry using anti-CD54+CD38+ and IgA/M/G antibodies, respectively. After stimulation of macrophages by IgG type immune complex, TNF-α and IL-6 levels were evaluated by ELISA. After co-incubation of microvascular endothelial cells with TNF-α or IL-6, the expressions of endothelial protein C receptor (EPCR) and thrombomodulin (TM), and the activity of activated protein C (APC) were examined. As the results showed, the IgG type plasma cells infiltration and the quantity of IgG type immune complex were increased in DSS group in comparison with control group. After incubation with IgG type immune complex, the levels of TNF-α and IL-6 in the supernatant of macrophages were increased (P < 0.01) in a concentration-dependent manner. Meanwhile, after incubation with TNF-α or IL-6, the expressions of EPCR and TM in the microvascular endothelial cells were decreased (P < 0.05 or P < 0.01), while the activity of APC was reduced (P < 0.05 or P < 0.01). These results suggested that the quantity of IgG type plasma cells increases in UC and forms immune complexes, which affect the secretion of cytokines from macrophage, thereby affecting the function of endothelial cells and finally inhibiting PCS in UC. Therefore, plasma cell may be a novel target for the treatment of UC.

Key words: plasma cell; ulcerative colitis ; immune complex ; Macrophage ; protein C system

收稿日期：2016-08-01　　录用日期：2016-12-01

通讯作者：王慧超　　E-mail: uhchao@sina.com

引用本文：

林旭红, 郭俊玲, 温玉清, 李玉霞, 魏丹丹, 杨瑞林, 穆小云, 王慧超. IgG型浆细胞在溃疡性结肠炎小鼠蛋白C系统变化中的作用[J]. 生理学报 2017; 69 (2): 172-182.

LIN Xu-Hong, GUO Jun-Ling, WEN Yu-Qing, LI Yu-Xia, WEI Dan-Dan, YANG Rui-Lin, MU Xiao-Yun, WANG Hui-Chao. Role of IgG plasma cells in the change of protein C system in ulcerative colitis. Acta Physiol Sin 2017; 69 (2): 172-182 (in Chinese with English abstract).