慢性胃炎患者胃黏膜菌群定位及定量分析

Locating and quantifying gastric mucosal microbiota of patients with chronic gastritis

目的对慢性胃炎患者胃黏膜菌群进行定位及定量分析,探究其与胃炎及幽门螺杆菌(Helicobacter pylori,H.pylori)感染的相关性。方法收集58例慢性胃炎患者胃黏膜标本,提取胃黏膜菌群DNA,行荧光定量PCR定量胃黏膜总细菌及H.pylori,并进行相关性分析;另收集12例慢性胃炎患者胃黏膜标本石蜡包埋切片行荧光原位杂交定位胃黏膜菌群;慢性胃炎、肠化生程度的分类依据新悉尼分类系统。结果慢性胃炎患者胃黏膜细菌主要分布于胃黏膜表面、胃小凹及腺体中,细菌单个散在分布或聚集成团。多元线性回归分析显示胃黏膜总细菌数与性别、年龄、肠化生程度无关,与H.pylori感染、慢性胃炎程度有关(P<0.05)。H.pylori阳性组胃黏膜总细菌数与H.pylori细菌数目呈明显正相关(r=0.536,P<0.01)。不同胃炎程度之间胃黏膜总细菌数差异有统计学意义(P<0.05),其中重度胃炎组胃黏膜总细菌数明显高于轻、中度胃炎组(P<0.05、0.01)。不同肠化生程度之间胃黏膜总细菌数差异无统计学意义(P>0.05)。H.pylori阳性组胃黏膜总细菌数明显高于阴性组(P<0.01)。结论慢性胃炎患者胃黏膜菌群主要分布于胃黏膜表面、胃小凹及腺体中,细菌单个散在分布或聚集成团。胃黏膜菌群与慢性胃炎程度、H.pylori感染有关,与性别、年龄、肠化生程度无关,提示胃黏膜菌群的改变参与慢性胃炎的发展,H.pylori感染可改变胃黏膜菌群。

Objective To locate and quantify gastric mucosal microbiota of patients with chronic gastritis,and explore its relationship with gastritis and Helicobacter pylori（ H. pylori） infection. Methods The microbiota DNA was extracted from the gastric mucosal biopsy specimens of 58 patients with chronic gastritis to quantify the total gastric bacteria and H. pylori using fluorogenic quantitative PCR. The gastric mucosa of another 12 patients with chronic gastritis were embedded in paraffin and cut into slices to locate the gastric microbiota using Fluorescence in situ hybridization. The grading of chronic gastritis and intestinal metaplasia was based on the updated Sydney System. Results The gastric microbiota of patients with chronic gastritis mainly located on the surface of epithelial cells,gastric pits and in the glands,and distributed separately,scatteredly or gathered in clusters. Multiple linear regression analysis showed that the total number of bacteria was associated with H. pylori infection and the degree of chronic gastritis（ P〈 0. 05）,wheras irrelevant to sex,age and the grade of intestinal metaplasia. In H. pylori positive group,it was positively correlated with the H. pylori number（ r = 0. 536,P〈 0. 01）. The total number of bacteria was different in three groups of gastritis,and that of the severe gastritis group was significantly higher than those of the mild and moderate groups（ P〈 0. 05,0. 01）. It was significantly higher in H. pylori positive group than in negative group（ P〈 0. 01）. Conclusion The gastric microbiota of patients with chronic gastritis mainly locate on the surface of epithelial cells,gastric pits and in the glands,and distribute separately,scatteredly or gather in clusters. Gastric microbita is associated with H. pylori infection and the grade of chronic gastritis,suggesting the alteration of gastric microbiota may involve in the development of chronic gastritis. H. pylori infection can change gastric microbiota.