幽门螺杆菌vacA基因型及其表达产物与胃十二指肠疾病关系的研究

A study on correlation between vacA genotypes and its expression products of H pylori, and gastroduodenal diseases

目的 探讨幽门螺杆菌vacA基因型及其表达产物———VacA与胃十二指肠疾病之间的关系。方法 用聚合酶链反应技术测定 62株从慢性胃炎、消化性溃疡和胃癌患者中分离获得的幽门螺杆菌 (Hp)菌株的vacA基因型 ;用Hela细胞测定Hp菌株体外VacA活性。 结果 62株Hp菌株均含有va cA基因 ,且VacA基因型均为sla/m2型。Hp产生VacA的阳性率为 3 7.1% ,慢性胃炎、消化性溃疡和胃癌患者感染Hp产生VacA的阳性率分别为 3 3 .3 3 %、2 9.17%和 63 .64 %。但是 ,此三种不同疾病患者感染Hp产生VacA的阳性率差异无显著性 (P >0 .0 5 )。 结论 Hp的vacA基因型、VacA并不能作为预示Hp感染个体更有可能发生慢性胃炎或消化性溃疡还是胃癌的可靠指标。本研究未能证实vacA基因型与Hp体外表达VacA的关系。

Objective To investigate the relationship between vacA genotypes of Helicobacter pylori (Hp) and its expression products vacuolating cytotoxin and gastroduodenal diseases. Methods vacA genotypes of 62 Hp strains isolated from patients with chronic gastritis, peptic ulcer and gastric cancer were tested by polymerase chain reaction and Hela cell assay for vacuolating cytotoxin activity in vitro. Results All 62 Hp strains possessed vacA gene and vacA genotypes of all strains were type sla/m2. The total positivity rate of VacA was 37.1%; the positivity rates of VacA produced by Hp strains isolated from patients with chronic gastritis, peptic ulcer and gastric cancer were 33.33%, 29.17% and 63.64%, respectively. There were no significant differences between the positivity rates of VacA produced by Hp strains isolated from patients with the above mentioned diseases ( P >0.05). Conclusions vacA genotypes of Helicobacter pylori and VacA can not predict subjects, infected with Helicobacter pylori who will be more likely to develop CG, PU or GC. The relationship between vacA genotypes of Hp and VacA can not be identified in this study.