BH3-only 蛋白 Bim与幽门螺杆菌诱导胃炎的严重程度相关

BH3-only 蛋白Bim,是一种促凋亡蛋白，介导线粒体依赖性细胞的凋亡。然而， Bim蛋白对幽门螺杆菌（Hp）相关性胃炎的作用仍不明确。该研究旨在评估Bim蛋白的细胞定位及其在Hp诱导的胃炎中可能的作用。

研究活检样本来自于80例(Hp阴性:n=30,Hp阳性: n=50)接受上消化道镜检的患者。通过免疫荧光染色检测Bim蛋白的定位，进而评估Bim蛋白的表达和胃炎严重程度间的关系。由悉尼系统的定义所知，Bim蛋白的mRNA表达与胃炎的严重程度正相关。

研究通过免疫组织化学分析法证实：人类和小鼠的Bim蛋白在感染Hp的胃黏膜中表达显著高于未感染Hp的胃黏膜。Bim蛋白分布在感染Hp的消化道的固有层和黏膜下层的髓过氧化物酶-CD138-阳性细胞中，表明该蛋白主要表达于嗜中性粒细胞和浆细胞。

相反，Bim蛋白没有分布在CD20-，CD3-或 CD68-阳性细胞中。Bim蛋白在线粒体中表达，且与活化的Bax和cleaved-PARP部分共存。

综上，Bim蛋白在Hp相关胃炎中的嗜中性粒细胞和浆细胞中表达，通过特异性白细胞中的线粒体介导细胞凋亡，终止炎症应答。

BH3-only protein Bim is associated with the degreeof Helicobacter pylori-induced gastritis and islocalized to the mitochondria of inflammatory cells in the gastric mucosa

1, 2, 3,et al.

 1NagasakiUniversity Hospital, 1-7-1 Sakamoto, Nagasaki City, Nagasaki, 852-8501, Japan;Department of Tumor and Diagnostic Pathology, Atomic Bomb Disease Institute,1-12-4 Sakamoto, Nagasaki City, Nagasaki, 852-8523, Japan. 2AtomicBomb Disease Institute, 1-12-4 Sakamoto, Nagasaki City, Nagasaki, 852-8523,Japan.3NagasakiUniversity Hospital, 1-7-1 Sakamoto, Nagasaki City, Nagasaki, 852-8501, Japan.

ABSTRACT

BH3-only protein, Bim,is a pro-apoptotic protein that mediates mitochondria-dependent cell death.However, the role of Bim in Helicobacter pylori-associatedgastritis remains unclear. This study aimed to assess the cellular localizationof Bim and its possible role in H. pylori-inducedgastritis. The study was conducted on biopsy specimens obtained from 80patients who underwent upper gastrointestinal endoscopy (H. pylori-negative: n=30, positive: n=50). Associationbetween Bim mRNA expression and severity of gastritis was evaluated and thelocalization of Bim was examined by immunofluorescence. Bim mRNA expression waspositively correlated with the degree of gastritis, as defined by the Sydneysystem. Immunohistochemical analysis confirmed increased Bim expression in H. pylori-infected gastric mucosa compared with uninfectedmucosa in both humans and mice. Bim localized in myeloperoxidase- and CD138-positivecells of H. pylori-infected lamina propria andsubmucosa of the gastric tract, indicating that this protein is predominantlyexpressed in neutrophils and plasma cells. In contrast, Bim did not localize inCD20-, CD3-, or CD68-positive cells. Bim was expressed in the mitochondria,where it was partially co-localized with activated Bax and cleaved-PARP.In conclusion, Bim is expressed in neutrophils andplasma cells in H. pylori-associated gastritis,where it may participate in the termination of inflammatory response by causingmitochondria-mediated apoptosis in specific leucocytes.

原文来源：Int J Med Microbiol. 2015 Sep;305(6):553-62. doi:10.1016/j.ijmm.2015.07.002. Epub 2015 Jul 9

来源：消化最前沿编译