Molecular Biology Department, Pasteur Institute of Iran, Tehran, Iran.
Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
Iran Biomed J. 2021 Jan;25(1):41-6. doi: 10.29252/ibj.25.1.41. Epub 2020 Jan 4.
Pasteurella multocida is a Gram-negative, non-motile, non-spore forming, and aerobic/anaerobic cocobacillus known as the causative agent of human and animal diseases. Humans can often be affected by cat scratch or bite, which may lead to soft tissue infections and in rare cases to bacteremia and septicemia. Commercial vaccines against this agent include inactivated, live attenuated, and non-pathogenic bacteria. Current vaccines have certain disadvantages such as reactogenicity or reversion to virulence. Therefore, the aim of this study was to reach a multi-epitope vaccine candidate that could be serotype independent and covers most incident serotypes of P. multocida.
In this study, reverse vaccinology strategy was used to identify potentially immunogenic and protective epitopes. First, multiple alignments of different sequences of Pasteurella lipoprotein E (PlpE) from various serotypes of P. multocida were analyzed to identify the conserved regions. Bioinformatics tools were then applied to predict and select epitopes for further studies.
Three different conserved immunogenic regions were selected according to the selected criteria, and their various sequential orders were evaluated structurally by in silico tools to find the best order.
In searching the epitopes of PlpE to design a new vaccine candidate against pasteurellosis, we found the region 1 + region 2 + region 3 (without any linker between regions) of epitope, including the regions of PlpE protein of P. multocida, as the appropriate serotype independent vaccine candidate against pasteurellosis.
多杀巴斯德菌是一种革兰氏阴性、非运动性、非孢子形成、需氧/厌氧球杆菌，是人类和动物疾病的病原体。人类通常会因猫抓伤或咬伤而感染，这可能导致软组织感染，极少数情况下还会导致菌血症和败血症。针对该病原体的商业疫苗包括灭活疫苗、减毒活疫苗和非致病性细菌。目前的疫苗存在一定的缺点，如反应原性或回复毒力。因此，本研究的目的是开发一种多表位疫苗候选物，该候选物可以与血清型无关，并涵盖大多数多杀巴斯德菌的偶发血清型。
在这项研究中，反向疫苗学策略被用于鉴定潜在的免疫原性和保护性表位。首先，对来自不同多杀巴斯德菌血清型的脂蛋白 E（PlpE）的多个序列进行多重比对，以鉴定保守区域。然后应用生物信息学工具来预测和选择表位进行进一步研究。
根据选定的标准选择了三个不同的保守免疫原性区域，并通过计算工具评估了它们的各种顺序结构，以找到最佳的顺序。
在搜索 PlpE 的表位以设计针对巴氏杆菌病的新型疫苗候选物时，我们发现包括多杀巴斯德菌 PlpE 蛋白区域在内的表位的区域 1+区域 2+区域 3（区域之间没有任何连接子），是针对巴氏杆菌病的合适的与血清型无关的疫苗候选物。
