在持续感染和慢性炎症中,Helicobacter pylori SabA粘附在持续感染和慢性炎症中
Jafar Mahdavi1, Berit Sondén, Marina Hurtig
1Department of Odontology/Oral Microbiology, Umeå University, SE-901 87 Umeå, Sweden.
概括
杆菌使用sialyl-Lewis x glycosphingolipids作为胃中的受体. 这种结合由酸结合粘合素 (SabA) 介导,有助于细菌的毒性和慢性感染.
科学领域:
- 微生物学 微生物学
- 免疫学 免疫学 免疫学
- 葡萄糖生物学 葡萄糖生物学
背景情况:
- 杆菌 (H. pylori) 感染是胃炎和胃潰瘍的主要原因.
- 细菌粘附于胃粘膜对于H. pylori的殖民和毒性至关重要.
- 特定的粘附蛋白和宿主受体介导H. pylori的附着.
研究的目的:
- 为了确定H. pylori粘附的特定宿主受体.
- 描述参与与这种受体结合的细菌粘合素.
- 为了研究这种相互作用在H. pylori感染和毒性中的作用.
主要方法:
- 鉴定sialyl-dimeric-Lewis x glycosphingolipid作为H.pylori的受体. 这是一个很好的方法.
- 使用"重新标记"方法分离酸结合粘合素 (SabA).
- 对sabA基因的鉴定 (JHP662/HP0725).
- 在H.pylori感染期间诱导的Sialyl-Lewis x抗原形成的证明 in vivo.
主要成果:
- Sialyl-dimeric-Lewis x glycosphingolipid被确定为H. pylori的一个关键宿主受体.
- 杆菌感染诱导了人类和 rhesus 子的胃上皮质中 sialyl-Lewis x 抗原的形成.
- 确定了酸结合粘合素 (SabA) 和相应的sabA基因.
结论:
- 由SabA介导的H. pylori和sialyl-Lewis x抗原之间的相互作用是H. pylori病变的一个重要因素.
- 这种粘附机制可能有助于细菌建立慢性感染的能力.
- 针对这种粘附-受体相互作用,可能会提供针对H. pylori的新治疗策略.
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