摘要
目的 幽门螺杆菌 (Hp)cag致病岛 (cagPAI)含 30多个基因 ,HpcagⅠ与cagⅡ中许多基因能增加胃上皮白细胞介素 8(IL 8)基因转录与IL 8蛋白分泌。本研究观察HpcagⅡ中ORF10基因对胃上皮细胞IL 8基因转录的影响 ,以验证HpcagPAI中某些基因下调IL 8基因转录及表达的可能性。方法 构建cagⅡORF10基因缺失 ( ORF10 )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 3株 ORF10Hp菌株 (2 8 1,2 8 2 ,2 8 3)诱导荧光素酶活性较亲代菌株 2 6 6 95显著增加 [分别为 2 8 1:(1.4 9± 0 .2 7)× 10 6cpm ,2 8 2 :(1.33± 0 .2 8)× 10 6cpm ,2 8 3:(1.33± 0 .2 9)× 10 6cpm ;亲代菌株2 6 6 95 :(0 .6 7± 0 .0 8)× 10 6cpm ;P分别 <0 .0 1,0 .0 5和 0 .0 5 ];2株 ORF10Hp菌株诱导IL 8蛋白水平较亲代菌株 2 6 6 95均显著升高 [分别为 2 8 2 :(1.2± 0 .0 8)ng/ml;2 8 3为 (1.2 4± 0 .0 7)ng/ml;亲代菌株 2 6 6 95为 (0 .33± 0 .19)ng/ml,P <0 .0 5 ,<0 .0 1]。结论 与HpcagⅠ与cagⅡ中大多数基因上调IL 8转录不同 ,cagⅡ中ORF10基因对胃上皮细胞IL
Objective Helicobacter pylori (H. pylori )contains more than 30 genes and many of them in cag pathogenicity island (cag PAI) composed of cag Ⅰ and cag Ⅱ are involved in eliciting the transcription of interleikin 8 (IL 8) and the induction of IL 8 protein secretion in gastric epithelial cells, although some genes are not involved. This study was designed to observe the effect of ORF10 of H. pylori cag Ⅱ on the transcription of IL 8 in gastric epithelial cells and to test the possibility that certain genes in the cag PAI also downregulate (modulate) the transcription and expression of IL 8 in gastric epithelial cells. Methods Three strains of H. pylori mutants with deletion of ORF10 gene (ORF10, namely 28 1, 28 2, 28 3) and L5F11 cells containing IL 8 reporter gene were constructed. The constructed L5F11 cells were co cultured with the above strains and the luciferase activity (IL 8 transcription) was measured in a scintillation counter and the concentration of IL 8 protein was assayed by enzyme linked immunosorbent assay (ELISA). Results The activities of luciferase induced by 3 strains of H. pylori mutants with deletion of ORF10 gene were much higher than that of the mother strain 26695 [ 28 1:(1.49 ± 0.27)×10 6 cpm vs. (0.67 ± 0.08 )× 10 6 cpm, P <0.01; 28 2:(1.33 ± 0.28)×10 6 cpm vs.(0.67 ± 0.08)×10 6 cpm, P <0.05;28 3:(1.33 ± 0.29)× 10 6 cpm vs. (0.67 ± 0.08)× 10 6 cpm, P <0.05, respectively]; The concentration of IL 8 protein induced by 2 strains of H. pylori mutants with deletion of ORF10 gene were also higher than that of the mother strain 26695[28 2:(1.2 ± 0.08) ng/ml vs.( 0.33 ± 0.19)ng/ml, P <0.05;28 3:(1.24 ± 0.07)ng/ml vs.( 0.33 ± 0.19)ng/ml, P <0.01, respectively]. Conclusions In contrast to the most genes of cag Ⅰ and cag Ⅱof H. pylori which upregulated the transcription of IL 8, ORF10 downregulated the transcription of IL 8 in gastric epithelial cells.
出处
《中华消化杂志》
CAS
CSCD
北大核心
2003年第3期158-160,共3页
Chinese Journal of Digestion
基金
欧共体资助课题(IC18CT95 0 0 2 4)