Rapid genetic analysis of Helicobacter pylori gastric mucosal colonization in suckling mice
Rapid genetic analysis of Helicobacter pylori gastric mucosal colonization in suckling mice
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DOI：
10.1073/pnas.122244899
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发表时间：
2002-06-11
影响因子：
11.1
通讯作者：
Mekalanos, JJ
中科院分区：
文献类型：
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作者：
Guo, BP;Mekalanos, JJ
先前描述的幽门螺杆菌感染的动物模型受到繁琐的宿主要求（例如，无菌条件或不常见的物种）或仅适用于H.幽门螺杆菌菌株（例如，新鲜的临床分离物或动物适应性衍生物）。在这里，我们报告说，5至6日龄的远交CD-1（ICR）乳鼠支持24小时的所有H。检测的幽门螺杆菌菌株（SS 1、26695 SmR-1、43504 SmR-1和G27 SmR-1），包括无法适应成年动物定植的实验室传代菌株。从实验室传代菌株感染中回收的总菌落形成单位（cfu）与小鼠适应的SS 1没有差异。我们还通过与野生型H. pylori和测量差异恢复。该竞争测定法鉴定了几类已知减毒突变体中的定殖缺陷，包括那些在耐酸性（ureA）、代谢（frdA）、运动性（motB）和趋化性（cheY）方面有缺陷的突变体。copA（铜转运P型ATP酶）缺陷突变体在成年和幼年小鼠中未减毒。可能是因为感染的持续时间有限，我们的模型没有确定空泡细胞毒素（vacA）或γ-谷氨酰转肽酶（ggt）的缺陷作为衰减，与其他动物模型的结果相反。我们还确定了一个新的毒力基因（HP0507）编码一个保守的假设蛋白，这是重要的殖民在我们的模型。乳鼠模型提供了一种快速的方法来鉴定任何H. pylori菌株，并可能作为研究原发感染免疫的新工具。
Previously described animal models for Helicobacter pylori infection have been limited by cumbersome host requirements (e.g., germ-free conditions or unusual species) or are applicable to only special subsets of H. pylori strains (e.g., fresh clinical isolates or animal-adapted derivatives). Here, we report that 5- to 6-day-old outbred CD-1 (ICR) suckling mice support 24-h colonization of all H. pylori strains tested (SS1, 26695 SmR-1, 43504 SmR-1, and G27 SmR-1), including lab-passaged strains that cannot be adapted for colonization of adult animals. Total colony-forming units (cfu) recovered from infection with lab-passaged strains did not differ from those with mouse-adapted SS1. We also tested this model's ability to detect colonization defects in strains carrying mutations in known virulence genes by coinfecting with wild-type H. pylori and measuring differential recovery. This competition assay identified colonization defects in several classes of known attenuated mutants, including those defective in acid resistance (ureA), metabolism (frdA), motility (motB), and chemotaxis (cheY). A mutant defective in copA (copper transporting P-type ATPase) is nonattenuated in adult and infant mice. Possibly because of the limited duration of infection, our model did not identify defects in vacuolating cytotoxin (vacA) or gamma-glutamyltranspeptidase (ggt) as attenuating, in contrast to results from other animal models. We also identified a new virulence gene (HP0507) encoding a conserved hypothetical protein, which is important for colonization in our model. The suckling mouse model offers a rapid method to identify colonization defects in any H. pylori strain and may have utility as a new tool for studying immunity to primary infection.