Classification of VacA,a cytotoxin produced by Helicobacter pylori, based on gene analyzes

基于基因分析的幽门螺杆菌产生的细胞毒素 VacA 的分类

• 批准号: 08670562
• 负责人: YOSHIDA Haruhiko
• 金额: $ 1.6万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08670562/
• 关键词: Helicobacter pylori; Vacuolating cytotoxin; recombinant VacA; Virulence factor; VacA; vacuolation; sequencing; antibody

Clinical features of Helicobacter pylori infection vary widely among patients. Production of the cytotoxin VacA has been alleged to be responsible for virulence by several reports from Western countries. This research sought to confirm the VacA-related virulence in Japan.This research has revealed, however, that most H.pylori isolates in Japan are positive for VacA irrespective of gastroduodenal status in the hosts. The cytotoxin activity in the supernatant of bacterial culture was usually positive, and the nucleotide sequence analysis of vacA gene revealed cytotoxinsecreting genotype. By using recombinant VacA expressed in E.coli, we further confirmed the production of VacA by bacterial isolates and the seropositivity of anti-VacA antibody in Japanese patients.It was concluded that VacA is not the major virulence determinant factor in Japan. However, the high prevalence of VacA-positive strains may be related to the high incidence of gastric cancer in Japan.

幽门螺杆菌感染的临床特征在患者之间差异很大。西方国家的一些报告称，细胞毒素 VacA 的产生是造成毒力的原因。这项研究旨在确认日本的 VacA 相关毒力。然而，这项研究表明，日本的大多数幽门螺杆菌分离株对 VacA 呈阳性，无论宿主的胃十二指肠状态如何。细菌培养上清液中细胞毒素活性通常呈阳性，vacA基因的核苷酸序列分析揭示了细胞毒素分泌基因型。通过使用在大肠杆菌中表达的重组VacA，我们进一步证实了细菌分离株产生VacA以及日本患者抗VacA抗体的血清阳性。得出结论VacA不是日本的主要毒力决定因素。然而，VacA阳性菌株的高患病率可能与日本胃癌高发有关。

项目成果

Ogura K, Kanai F, Yoshida H, Shiratori Y, et al.: "High prevalence of cytotoxin positive Helicobacter pylori in patients unrelated to the presence of peptic ulcers in Japan." GUT. 41. 463-468 (1997)

Ogura K、Kanai F、Yoshida H、Shiratori Y 等人：“在日本，与消化性溃疡无关的患者中细胞毒素阳性幽门螺杆菌的患病率很高。”

Maeda S,Yoshida H,Kanai F,Kato N,Shiratori Y,et al.: "Major virulence factors, VacA and CagA,are commonly positive in Helicobacter pylori isolates in Japan." GUT. (in press). (1998)

Maeda S、Yoshida H、Kanai F、Kato N、Shiratori Y 等人：“日本幽门螺杆菌分离株中的主要毒力因子 VacA 和 CagA 通常呈阳性。”

Kawamata O, Yoshida H, Shiratori Y, et al.: "Nested-polymerase.chain reaction assay for the detection of Helicobacter pylori nfection with novel primers designed by sequence analysis of urease A gene in clinically isolated bacterial strains." Biochemica a

Kawamata O、Yoshida H、Shiratori Y 等人：“通过对临床分离的细菌菌株中的脲酶 A 基因进行序列分析而设计的新型引物，用于检测幽门螺杆菌感染的巢式聚合酶链式反应测定。”

小椋啓司、金井文彦、前田悦、白鳥康史、小俣政男: "VacA遺伝子の多様性と疾病" 内科. 78巻1号. 71-75 (1996)

Keiji Ogura、Fumihiko Kanai、Etsu Maeda、Yasushi Shiratori、Masao Omata：“VacA 基因多样性与疾病”，第 78 卷，第 1. 71-75 期（1996 年）。

Maeda S, kanai F, Yoshida H, Shiratori Y, et al.: "High seropositivity of anti-CagA antibody in Helicobacter pylori-infected patients irrelevant to peptic ulcers and normal mucosa in Japan." Digestive Diseases and Science. 42. 1841-1847 (1997)

Maeda S、kanai F、Yoshida H、Shiratori Y 等人：“日本幽门螺杆菌感染患者的抗 CagA 抗体血清呈高阳性，与消化性溃疡和正常粘膜无关。”