Shiga toxin-producing Escherichia coli:: An overview
Shiga toxin-producing Escherichia coli:: An overview
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DOI：
10.2527/jas.2006-508
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发表时间：
2007-03-01
影响因子：
3.3
通讯作者：
Gyles, C. L.
中科院分区：
文献类型：
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作者：
Gyles, C. L.
该综述的目的是强调牛在人类疾病中的重要性，并讨论产生志贺毒素的大肠杆菌(STEC)在人类疾病中的重要特征。健康的奶牛和肉牛是各种STEC的主要宿主，STEC通过食物和水的污染以及直接接触感染人类。人类感染STEC可能会导致水样腹泻、血性腹泻和溶血性尿毒症综合征的组合。STEC的血清型、亚型和毒力分型系统用于流行病学、诊断和发病机制研究。严重疾病和疾病暴发最常见的原因是O157：H7血清型，与大多数其他高致病性STEC一样，它通过一种特有的附着和消退病变的方式在大肠定植。这种损害是由细菌III型分泌系统引起的，该系统将效应蛋白注入肠道上皮细胞，导致宿主细胞的结构和代谢发生深刻变化，并使细菌紧密黏附。以血性腹泻和溶血性尿毒症综合征为形式的严重疾病可归因于志贺毒素(STX)，它以STX1和STX2两种主要类型存在。STX基因编码在细菌染色体上的温和噬菌体上，毒素的产生和释放高度依赖于噬菌体的诱导。参与附着和消退损伤诱导的基因调控和STX的产生是复杂的。除了这些明显与毒力有关的基因外，还有几个假定的毒力因素。一个主要的公共卫生目标是预防STEC引起的人类疾病。旨在了解影响牛携带和脱落STEC的因素以及促进人类疾病发展的因素的研究被认为是实现这一目标的重要因素。
The objective of this review is to highlight the importance of cattle in human disease due to Shiga toxin-producing Escherichia coli (STEC) and to discuss features of STEC that are important in human disease. Healthy dairy and beef cattle are a major reservoir of a diverse group of STEC that infects humans through contamination of food and water, as well as through direct contact. Infection of humans by STEC may result in combinations of watery diarrhea, bloody diarrhea, and hemolytic uremic syndrome. Systems of serotyping, subtyping, and virulence typing of STEC are used to aid in epidemiology, diagnosis, and pathogenesis studies. Severe disease and outbreaks of disease are most commonly due to serotype O157: H7, which, like most other highly pathogenic STEC, colonize the large intestine by means of a characteristic attaching and effacing lesion. This lesion is induced by a bacterial type III secretion system that injects effector proteins into the intestinal epithelial cell, resulting in profound changes in the architecture and metabolism of the host cell and intimate adherence of the bacteria. Severe disease in the form of bloody diarrhea and the hemolytic uremic syndrome is attributable to Shiga toxin (Stx), which exists as 2 major types, Stx1 and Stx2. The stx genes are encoded on temperate bacteriophages in the chromosome of the bacteria, and production and release of the toxin are highly dependent on induction of the phages. Regulation of the genes involved in induction of the attaching and effacing lesion, and production of Stx is complex. In addition to these genes that are clearly implicated in virulence, there are several putative virulence factors. A major public health goal is to prevent STEC-induced disease in humans. Studies aimed at understanding factors that affect carriage and shedding of STEC by cattle and factors that contribute to development of disease in humans are considered to be important in achieving this objective.