Xie X F, Ito M, Sumii M, Tanaka S, Yoshihara M, Chayama K
Department of Medicine and Molecular Science, Hiroshima University, Hiroshima, Japan.
Pathobiology. 2007;74(5):309-16. doi: 10.1159/000105814.
Cytotoxin-associated gene A (cagA) is the major virulence factor of Helicobacter pylori strains and affects the clinical outcome of patients. Blood group antigen binding adhesin (BabA) helps the strains adhere to the epithelial cell layer and is the most important adhesin of H. pylori.
We tried to study the association between the status of babA2 and cagA in H. pylori strains and histological gastritis. methods: Thirty-six patients were included. RNA was extracted from two frozen biopsy samples of the antrum and corpus, respectively, and cagA/babA2 genotypes were analyzed with reverse transcription polymerase chain reaction and direct sequencing. Two gastric specimens of the antrum and corpus, respectively, were also stained with hematoxylin and eosin to analyze H. pylori-related gastritis.
In the antrum, 56% of the specimens were babA2 positive and in the corpus 53%. The gastritis scores of activity and inflammation were associated with the presence of babA2 in antrum specimens but not in corpus specimens. cagA gene encoding in the CagA EPIYA-D region was detected in all samples, and the sequence was completely identical between those from the gastric corpus and antrum.
babA2 expression is heterogeneous and correlated with the extent of gastritis in the antrum, but not in the corpus, whereas cagA shows a monotonous genotype.
细胞毒素相关基因A(cagA)是幽门螺杆菌菌株的主要毒力因子,影响患者的临床结局。血型抗原结合黏附素(BabA)有助于菌株黏附于上皮细胞层,是幽门螺杆菌最重要的黏附素。
我们试图研究幽门螺杆菌菌株中babA2和cagA状态与组织学胃炎之间的关联。方法:纳入36例患者。分别从胃窦和胃体的两份冷冻活检样本中提取RNA,采用逆转录聚合酶链反应和直接测序分析cagA/babA2基因型。胃窦和胃体的两份胃标本也分别用苏木精和伊红染色,以分析幽门螺杆菌相关性胃炎。
在胃窦中,56%的标本babA2呈阳性,在胃体中为53%。胃窦标本中活动度和炎症的胃炎评分与babA2的存在相关,而胃体标本中则不然。所有样本中均检测到CagA EPIYA-D区域编码的cagA基因,胃体和胃窦样本的序列完全相同。
babA2表达具有异质性,与胃窦而非胃体的胃炎程度相关,而cagA表现出单一的基因型。