Peña Jessy, Rojas Héctor, Reyes Nelson, Fernández-Delgado Milagro, García-Amado María-Alexandra, Michelangeli Fabián, Contreras Monica
Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
Instituto de Inmunología, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela.
J Med Microbiol. 2017 Mar;66(2):226-235. doi: 10.1099/jmm.0.000409. Epub 2017 Mar 6.
Multiple Helicobacter pylori strains colonize and coexist in the stomach of one single patient, carrying heterogeneous distributions of cag genotypes. The oesophagus provides a niche for H. pylori colonization; however, little is known about its adaptive role.
Using PCR for cagA, cagE and virB11 genes from cag-pathogenicity island (PAI) and Etest for antimicrobial susceptibility test, we determined cag-PAI genotypes associated with H. pylori virulence, when positive cultures were matching in both the stomach and the oesophagus (96 isolates; 8 out of 80 dyspeptic patients).
The stomach showed complete cag-PAI islands in 77 % of the isolates, whereas the oesophagus showed complete cag-PAI islands only in 44 % of the isolates. Expression of CagA and interleukin 8 correlated with inflammatory processes and histopathological changes in the stomach, but not in the oesophagus. Different cag-PAI profiles were found in both mucosae of an individual host, and at least one oesophagus profile corresponded to one profile identified in stomach. The antibiotic resistance profiles showed variability in the colonization by single or mixed H. pylori isolates in the gastric and oesophageal mucosa both intra- and inter-individuals.
These results demonstrate colonization with multiple H. pylori isolates in the oesophageal mucosa, like those found in the stomach of individual hosts. H. pylori was characterized by a dominant partial island, low interleukin 8 induction with lower histopathological damage and lower antibiotic resistance, suggesting that the microenvironmental changes in individual hosts select less virulent isolates in the oesophagus than in the stomach. New approaches to ensure effective eradication therapy in multi-resistant H. pylori strains must be developed.
多种幽门螺杆菌菌株可在同一患者胃内定植并共存，其细胞毒素相关基因（cag）基因型分布各异。食管为幽门螺杆菌定植提供了一个生态位；然而，其适应性作用却鲜为人知。
采用聚合酶链反应（PCR）检测来自cag致病岛（PAI）的cagA、cagE和virB11基因，并使用Etest进行药敏试验，当胃和食管的阳性培养物匹配时（96株分离株；80例消化不良患者中的8例），我们确定了与幽门螺杆菌毒力相关的cag-PAI基因型。
77%的胃内分离株显示完整的cag-PAI岛，而食管内分离株仅44%显示完整的cag-PAI岛。CagA和白细胞介素8的表达与胃内的炎症过程和组织病理学变化相关，但与食管内的无关。在个体宿主的两种黏膜中发现了不同的cag-PAI谱，并且至少有一种食管谱与胃内鉴定出的一种谱相对应。抗生素耐药谱显示，在个体内部和个体之间，胃和食管黏膜中单一或混合的幽门螺杆菌分离株定植存在差异。
这些结果表明，食管黏膜中存在多种幽门螺杆菌分离株定植，如同在个体宿主胃内发现的情况一样。幽门螺杆菌的特征是存在一个占主导地位的部分岛，白细胞介素8诱导水平较低，组织病理学损伤较小，抗生素耐药性较低，这表明个体宿主中的微环境变化在食管中选择的毒力较低的分离株比在胃中少。必须开发新的方法来确保对多重耐药幽门螺杆菌菌株进行有效的根除治疗。
