Immunogenicity of recombinant porcine attaching and effacing-associated protein compared with intimin fragment in Escherichia coli O157:H7-infected mice.
Immunogenicity of recombinant porcine attaching and effacing-associated protein compared with intimin fragment in Escherichia coli O157:H7-infected mice.
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重组猪附着和擦除相关蛋白与大肠杆菌 O157:H7 感染小鼠中的 intimin 片段相比的免疫原性。
DOI：
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发表时间：
2013
影响因子：
2.8
通讯作者：
Hui Wang
中科院分区：
文献类型：
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作者：
Tao Li;Ran Han;Qin Wang;Sheng;Huali Fang;Zhanqi Li;Wei Tu;Dehui Wang;Hui Wang
肠出血性大肠杆菌（EHEC）引起广泛的食物和水传播的传染病，包括腹泻，出血性结肠炎，甚至溶血性尿毒症综合征。猪附着和消失相关蛋白（Porcine attaching and effacing-associated protein，Paa）是在一株猪致病性大肠杆菌中首次发现的。大肠杆菌菌株。它在EHEC的粘附和清除机制中起着重要作用。然而，Paa蛋白的免疫功能尚未确定。在本研究中，重组Paa蛋白在工程菌E. coli中，并有效纯化至均一。以已知的粘附因子（intimin）为参照，在小鼠中进行比较实验，以研究Paa的免疫原性。腹腔免疫小鼠的Paa蛋白通过Th 2介导的体液免疫应答引起显着高水平的血清免疫球蛋白G抗体。在E.大肠杆菌O 157：H7，Paa蛋白具有抗病原菌定植和排泄的免疫学效应。与intimin相比，Paa对E.大肠杆菌O 157：H7感染的小鼠，特别是那些用高致死剂量的病原体攻击的小鼠。在Paa组中，70%的小鼠在50最小致死剂量（MLD）下存活，而在intimin组中只有50%存活。这一发现是对Paa蛋白免疫功能的首次描述。这些特性为开发基于Paa的疫苗提供了支持，该疫苗可用于治疗由E. coli O157：H7。
Enterohemorrhagic Escherichia coli (EHEC) causes a wide spectrum of food- and waterborne infectious diseases, including diarrhea, hemorrhagic colitis, and even hemolytic-uremic syndrome. Porcine attaching and effacing-associated protein (Paa) was first identified in a porcine enteropathogenic E. coli strain. It has been proven essential in the attaching and effacing mechanism of EHEC. However, the immunologic function of the Paa protein has yet to be established. In the present study, recombinant Paa protein was overexpressed successfully in engineered E. coli and effectively purified to homogeneity. Comparative experiments were carried out in mice with a known adhesion factor (intimin) as reference to investigate the immunogenicity of Paa. Intraperitoneal immunization of Paa protein in mice elicited significantly high levels of serum immunoglobulin G antibodies via Th2-mediated humoral immune response. In mice challenged with E. coli O157:H7, Paa protein exhibited immunological effectiveness against pathogenic bacteria colonization and excretion in vivo. Compared with the intimin, Paa showed better protective effect against E. coli O157:H7 infection in mice, particularly those challenged with high lethal doses of the pathogen. Seventy percent of the mice challenged with 50 minimal lethal dose (MLD) in the Paa group survived, whereas only 50% survived in the intimin group. This finding is the first description of the immunologic function of the Paa protein. These attributes provide support for the development of Paa-based vaccine, which can be beneficial in treating infectious diseases caused by E. coli O157:H7.