Marshall Barry
Helicobacter pylori Research Laboratory, Queen Elizabeth ll Medical Centre, Nedlands, Western Australia.
Clin Med (Lond). 2002 Mar-Apr;2(2):147-52. doi: 10.7861/clinmedicine.2-2-147.
Helicobacters are a new genus of bacteria, inhabiting the interface between mucosa and lumen of the gut. Microaerophilic, spiral, flagellated and urease positive, they possess features necessary for colonisation of the juxtamucosal mucus environment. Helicobacter pylori is the major pathogenic species. Once attached to the gastric epithelial cells, it incites an immune response characterised histologically by the development of active gastritis and immunologically by the presence of specific IgG. Persistence of infection is ensured by attachment to tissue antigens (eg Lewis B), a vacuolating toxin (VacA) which assists the free passage of urea through epithelial cells, and a cytotoxin (CagA) which is actually injected into the epithelial cells via a Type IV secretion system. Finally, during the typical lifelong chronic infection, two important diseases occur. H. pylori alters gastric physiology to cause acid hypersecretion and peptic ulcer. Secondly, it damages the acid secreting mucosa leading to atrophic gastritis and gastric cancer risk.
幽门螺杆菌是一种新的细菌属，栖息于肠道黏膜与管腔的界面。它们是微需氧菌，呈螺旋状，有鞭毛且尿素酶呈阳性，具备在近黏膜黏液环境中定殖所需的特征。幽门螺杆菌是主要的致病菌种。一旦附着于胃上皮细胞，它就会引发免疫反应，组织学上表现为活动性胃炎的发展，免疫学上表现为特异性IgG的存在。通过附着于组织抗原（如Lewis B）、一种协助尿素通过上皮细胞自由通透的空泡毒素（VacA）以及一种实际上通过IV型分泌系统注入上皮细胞的细胞毒素（CagA）来确保感染的持续存在。最后，在典型的终身慢性感染过程中，会发生两种重要疾病。幽门螺杆菌改变胃生理，导致胃酸分泌过多和消化性溃疡。其次，它会损害分泌酸的黏膜，导致萎缩性胃炎和胃癌风险。
