Diagnostic Strategy for Identifying Avian Pathogenic Escherichia coli Based on Four Patterns of Virulence Genes
Diagnostic Strategy for Identifying Avian Pathogenic Escherichia coli Based on Four Patterns of Virulence Genes
复制标题
DOI：
10.1128/jcm.05057-11
复制
发表时间：
2012-05-01
影响因子：
9.4
通讯作者：
Moulin-Schouleur, Maryvonne
中科院分区：
文献类型：
--
作者：
Schouler, Catherine;Schaeffer, Brigitte;Moulin-Schouleur, Maryvonne
为提高禽致病性大肠杆菌(APEC)菌株的鉴定水平，对1,491株APEC分离株进行了血清学分型、毒力基因分型和鸡致病性实验研究。这些分离株来自法国、西班牙和比利时的禽类大肠杆菌病皮损(n=1,307)或健康动物的肠道(n=184)。根据它们对雏鸡的毒力定义了该集合的一个子集(460个分离物)。O1、O2、O5、O8、O18和O78 6个血清群占APEC分离株的56.5%，占非致病株的22.5%。13个毒力基因在APEC分离株中的出现频率高于非致病分离株，但单独而言，没有一个基因能单独鉴定一个分离株为APEC株。为了考虑APEC菌株的多样性，对460株APEC致病和非致病分离株进行了基于树模型方法的统计分析。这导致了毒力基因的四种不同关联的鉴定，从而使70.2%的致病菌株得以鉴定。病原菌的鉴定误差为4.3%。这四种毒力模式和对鸡的致病性之间的联系的可靠性在收集的395个大肠杆菌分离株的样本上得到了验证。与兽医实验室目前使用的经典血清分型方法相比，这里描述的基因分型方法允许以更高的可靠性鉴定更多的APEC分离株。
In order to improve the identification of avian pathogenic Escherichia coli (APEC) strains, an extensive characterization of 1,491 E. coli isolates was conducted, based on serotyping, virulence genotyping, and experimental pathogenicity for chickens. The isolates originated from lesions of avian colibacillosis (n = 1,307) or from the intestines of healthy animals (n = 184) from France, Spain, and Belgium. A subset (460 isolates) of this collection was defined according to their virulence for chicks. Six serogroups (O1, O2, O5, O8, O18, and O78) accounted for 56.5% of the APEC isolates and 22.5% of the nonpathogenic isolates. Thirteen virulence genes were more frequently present in APEC isolates than in nonpathogenic isolates but, individually, none of them could allow the identification of an isolate as an APEC strain. In order to take into account the diversity of APEC strains, a statistical analysis based on a tree-modeling method was therefore conducted on the sample of 460 pathogenic and nonpathogenic isolates. This resulted in the identification of four different associations of virulence genes that enables the identification of 70.2% of the pathogenic strains. Pathogenic strains were identified with an error margin of 4.3%. The reliability of the link between these four virulence patterns and pathogenicity for chickens was validated on a sample of 395 E. coli isolates from the collection. The genotyping method described here allowed the identification of more APEC isolates with greater reliability than the classical serotyping methods currently used in veterinary laboratories.