[异常树突状细胞介导的内脏高敏感性大鼠模型免疫反应]

[Abnormal dendritic cells mediated immune response in a rat model of visceral hypersensitivity].

作者信息

Li Meng, Zhang Lu, Lü Bin, Meng Li-na, Chen Zhe, Chu Li

机构信息

Department of Gastroenterology, First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou 310006, China.

Department of Gastroenterology, First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou 310006, China. Email:

出版信息

Zhonghua Yi Xue Za Zhi. 2013 Sep 24;93(36):2904-8.

PMID:24373406

Abstract

OBJECTIVE

To explore the role of altered characteristics of intestinal dendritic cell (DC) in the induction of visceral hyperalgesia through the activation of mast cells in a rat model of irritable bowel syndrome (IBS).

METHODS

A total of 20 Sprague-Dawley rats were divided into modeling and control groups (n = 10 each). The IBS rat model was established by combining colorectal distention with restraint stress. Abdominal withdrawal reflex (AWR) was employed to evaluate visceral sensitivity. The surface marker of intestinal DC was analyzed by immunohistochemistry. Toluidine blue staining was used to determine the number of mast cells (MC). The expressions of interleukin (IL) -4 and IL-9 in colonic mucosa were measured by enzyme-linked immunosorbent assay (ELISA) and the level of proteinase-activated receptor-2 (PAR-2) was measured by Western blot. Mesenteric lymph node (MLN) DC and splenic CD4(+)/CD8(+)T cells were isolated and purified by magnetic label-based technique. Cytokine production of MLN DC co-culturing with CD4(+) or CD8(+)T cells was determined.

RESULTS

The number of colonic MC in modeling group was more than that in control group ((2.73 ± 0.21) vs (1.13 ± 0.10), P = 0.000). The expressions of PAR-2, IL-4 and IL-9 in colonic mucosa were all higher than those in control group (2.13 ± 0.81 vs 0.42 ± 0.29, (7.2 ± 1.2) vs (3.3 ± 1.0) pg/ml, (7.3 ± 1.3) vs (5.2 ± 0.6) pg/ml, P = 0.026, 0.000, 0.001). Co-cultured MLN DC with CD4(+) T cells showed a predominant IL-4 secretion in the modeling group ((1.22 ± 0.33) vs (0.80 ± 0.48) pg/ml, P = 0.000).

CONCLUSION

Increased colonic DC may stimulate CD4(+) T cells to secrete a high level of IL-4 to cause the degranulation of mast cells and the generation of visceral hypersensitivity in IBS rats.

摘要

目的

通过激活肥大细胞，探讨肠道树突状细胞（DC）特性改变在肠易激综合征（IBS）大鼠模型内脏高敏反应诱导中的作用。

方法

将20只Sprague-Dawley大鼠分为建模组和对照组（每组n = 10）。采用结直肠扩张联合束缚应激建立IBS大鼠模型。采用腹部退缩反射（AWR）评估内脏敏感性。通过免疫组织化学分析肠道DC的表面标志物。用甲苯胺蓝染色法测定肥大细胞（MC）数量。采用酶联免疫吸附测定（ELISA）法检测结肠黏膜中白细胞介素（IL）-4和IL-9的表达，并用蛋白质印迹法检测蛋白酶激活受体-2（PAR-2）的水平。采用基于磁珠标记的技术分离和纯化肠系膜淋巴结（MLN）DC和脾CD4(+)/CD8(+)T细胞。测定MLN DC与CD4(+)或CD8(+)T细胞共培养时细胞因子的产生情况。

结果

建模组结肠MC数量多于对照组（（2.73±0.21）对（1.13±0.10），P = 0.000）。结肠黏膜中PAR-2、IL-4和IL-9的表达均高于对照组（2.13±0.81对0.42±0.29，（7.2±1.2）对（3.3±1.0）pg/ml，（7.3±1.3）对（5.2±0.6）pg/ml，P = 0.026、0.000、0.001）。建模组MLN DC与CD4(+) T细胞共培养时IL-4分泌占优势（（1.22±0.33）对（0.80±0.48）pg/ml，P = 0.000）。