Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Sci Rep. 2017 Aug 14;7(1):8036. doi: 10.1038/s41598-017-08176-7.
The H. pylori outer inflammatory protein A (OipA) is an outer membrane protein that contributes to gastric inflammation. OipA is believed to affect intra-cellular signalling and modulate the host signalling pathways. The aim of the current study was to clarify the role of OipA in H. pylori pathogenesis and its effect on host cell signalling pathways. To this end, the oipA gene was isolated and inserted into cloning and expression vectors. The recombinant plasmid was transferred into an expression host to produce OipA, which was subsequently purified by affinity chromatography and used for antibody production. A confluent monolayer of gastric cell lines was treated with various concentrations of OipA and investigated for attachment, toxicity, and apoptosis and alterations in signalling pathways. OipA bound to gastric cell lines confirming its role in the attachment of H. pylori to host cells. The ratio of Bax/Bcl-2 and caspase3, 8, FasL in the host cells were assessed and the results showed that the Bax/Bcl-2 ratio as well as the level of cleaved-caspase 3 was elevated in OipA-treated cells. These findings suggest that OipA can bind and induce toxic events as well as triggering apoptotic cascade in host gastric cells through intrinsic pathway.
幽门螺杆菌外膜炎症蛋白 A（OipA）是一种外膜蛋白，有助于胃炎症。OipA 被认为影响细胞内信号转导并调节宿主信号通路。本研究旨在阐明 OipA 在幽门螺杆菌发病机制中的作用及其对宿主细胞信号通路的影响。为此，分离并插入克隆和表达载体中的 oipA 基因。将重组质粒转移到表达宿主中以产生 OipA，然后通过亲和层析进行纯化，并用于抗体生产。用不同浓度的 OipA 处理胃细胞系的汇合单层，并研究其附着、毒性和细胞凋亡以及信号通路的改变。OipA 与胃细胞系结合，证实其在幽门螺杆菌附着于宿主细胞中的作用。评估宿主细胞中 Bax/Bcl-2 和 caspase3、8、FasL 的比值，结果表明 OipA 处理的细胞中 Bax/Bcl-2 比值以及 cleaved-caspase 3 的水平升高。这些发现表明，OipA 可以通过内在途径结合并诱导宿主胃细胞中的毒性事件以及触发凋亡级联。
