Campbell S, Fraser A, Holliss B, Schmid J, O'Toole P W
Department of Microbiology and Genetics, Massey University, Palmerston North, New Zealand.
Infect Immun. 1997 Sep;65(9):3708-12. doi: 10.1128/iai.65.9.3708-3712.1997.
Helicobacter pylori infection in humans is linked to gastritis, gastric and duodenal ulcers, and gastric cancer. Peptic ulcer disease, as distinct from chronic asymptomatic infection, is strongly associated with expression of bacterial virulence markers, including a major antigen, CagA, and the vacuolating cytotoxin VacA. We have previously described significant differences in colonization rates, independent of socioeconomic status, among ethnic groups in New Zealand. To evaluate relative risks for peptic ulcer disease, we examined the frequency of two virulence markers in H. pylori strains infecting these ethnic groups. Although these markers occurred significantly more frequently in strains isolated from Polynesians than in strains from Europeans, this frequency was not reflected in the incidence of peptic ulcer disease in the two groups. DNA fingerprinting of the urease gene showed that Polynesians are more frequently infected by a group of strains which are genetically distinct from those affecting European New Zealanders. Our data suggest that separate bacterial lineages may have evolved in parallel with race-specific specialization.
人类感染幽门螺杆菌与胃炎、胃溃疡、十二指肠溃疡及胃癌有关。与慢性无症状感染不同，消化性溃疡疾病与细菌毒力标志物的表达密切相关，这些标志物包括一种主要抗原CagA和空泡毒素VacA。我们之前曾描述过，在新西兰，不同种族之间的幽门螺杆菌定植率存在显著差异，且与社会经济地位无关。为了评估消化性溃疡疾病的相对风险，我们检测了感染这些种族的幽门螺杆菌菌株中两种毒力标志物的出现频率。尽管这些标志物在从波利尼西亚人分离出的菌株中出现的频率明显高于从欧洲人分离出的菌株，但这一频率并未反映在两组消化性溃疡疾病的发病率上。脲酶基因的DNA指纹图谱显示，与感染新西兰欧洲人的菌株相比，波利尼西亚人更常感染一组基因不同的菌株。我们的数据表明，不同的细菌谱系可能是与种族特异性特化并行进化的。
