cagⅠ与cagⅡ在中国人群感染幽门螺杆菌中分布的差异及其与疾病的关系

目的 探讨cag致病岛的左右两部分cagⅠ与cagⅡ在中国人群感染幽门螺杆菌 (Hp)中的分布差异及其与Hp致病的相关性。 方法 采用PCR方法检测了 10 7例临床分离培养的Hp菌株 ,分别扩增cag致病岛的cagⅠ中的 170bp及cagⅡ中的 5 97bp片段。 结果 cagⅠ和cagⅡ均阳性的检出率为 6 1.7% ;单纯cagⅠ或cagⅡ的阳性检出率分别为 2 5 .2 %、7.5 % ;cagⅠ和cagⅡ均阴性的检出率为 5 .6 %。 结论 cagⅠ阳性检出率明显高于cagⅡ ,其差异主要存在于慢性胃炎中 (P <0 .0 1) ,在消化性溃疡等疾病中的检出无显著差异 (P >0 .0 5 )

幽门螺杆菌cagⅡ对胃上皮细胞IL-8基因转录的影响及机制

目的 探讨HpcagⅡ对胃上皮细胞IL 8基因转录的影响及信号传导机制。 方法 构建cagⅡ基因位点缺失Hp突变株及带有IL 8报告基因的人胃癌细胞系L5F11,用液体闪烁计数仪测定荧光素酶 (IL 8转录 )活性 ,用ELISA法测定IL 8蛋白浓度。结果 所有Hp突变株诱导荧光素酶活性与IL 8蛋白浓度较亲代菌株 2 6 6 95均降低 [(0 .13± 0 .0 1)× 10 6cpm比 (0 .5 9± 0 .0 5 )× 10 6cpm (P <0 .0 1) ;(0 .73± 0 .13)ng/ml比 (2 .2 2± 0 .6 5 )ng/ml,(P <0 .0 5 ) ]。PTK抑制剂herbimycinA不仅抑制Hp诱导的荧光素酶活性 [(0 .71± 0 .18)× 10 6cpm比 (1.5 1±0 .2 3)× 10 6cpm ,(P <0 .0 5 ) ],而且抑制IL 8蛋白表达 [(0 .83± 0 .41)ng/ml比 (3.2 2± 0 .5 9)ng/ml,(P <0 .0 5 ) ],但herbimycinA对TNFα诱导的荧光素酶活性及IL 8蛋白表达均无影响 (P均 >0 .0 5 ) ;PKA抑制剂H7抑制TNFα诱导的荧光素酶活性 [(0 .74± 0 .16 )× 10 6cpm比 (2 .6 2± 0 .2 6 )× 10 6cpm ,(P <0 .0 0 1) ]及IL 8蛋白表达 [(1.45±0 .38)ng/ml比 (4 .12± 0 .43)ng/ml,(P <0 .0 1) ],而对Hp诱导的荧光素酶活性无影响 (P >0 .0 5 )。 结论 HpcagⅡ中的多个基因能够调节胃上皮细胞IL 8基因转录 。

Gene distribution of cagII in Helicobacter pylori-infected patients of Zhejiang Province

AIM: To determine the prevalence of genotypes of cagⅡ in Helicobacter pylori( H pylon)-infected patients in Zhejiang Province and investigate the relationship between these genotypes and the types of gastroduodenal diseases.METHODS: One hundred and seventy one clinical isolates were collected from 70 chronic superficial gastritis, 31 chronic atrophic gastritis, 41 gastric ulcer, 21 duodenal ulcer, 3 gastric and duodenal ulcer, and 5 gastric adenocarcinoma patients. Polymerase chain reaction assays were performed for analysis of cagT, ORF13 and ORF10 genes in the cagⅡ region.RESULTS: Of 171 Hpyloriisolates from Zhejiang patients,159(93.0%) were positive for all the three loci. One isolate (0.6%) was negative for all the three loci, and 11(6.4%) were partially deleted in cagⅡ. The positive rates of cagT,ORF13 and ORF10 genes were 97.1%, 94.7% and 99.4%,respectively. In the strains isolated from the patients with diseases including chronic superficial gastritis, chronic atrophic gastritis, gastric ulcer and duodenal ulcer, the sitive rates of cagT were 95.7%, 100.0%, 95.1% and 100.0%, respectively. The positive rates of ORF13 were 94.3%, 93.5%, 95.1% and 100.0%, respectively. The sitive rates of ORF10 were 98.6%,100.0%,100.0% and 100.0%, respectively. The three genes were all positive in the three H pylori strains isolated from the patients with both gastric and duodenal ulcer. In the five strains isolated from the patients with gastric adenocarcinoma,only one isolate was negative for ORF13. There were no significant differences of the cagT, ORF13 and ORF10 genes among the different gastroduodenal diseases including chronic superficial gastritis, chronic atrophic gastritis,gastric ulcer, duodenal ulcer, both gastric and duodenal ulcer and gastric adenocarcinoma (χ^2=3.098, P＞0.05 for cagT;χ^2=3.935, P＞0.05 for ORF13 and χ^2=6.328,P＞0.05 for ORF10).CONCLUSION: The cagⅡ is not a uniform and conserved entity. Although the genes in cagⅡ are highly associated with the gastroduodenal diseases, the clinical outcome of Hpyloriinfection is not reliably predicted by the three genes in cagⅡ in patients from Zhejiang Province.