Cao Yimei, Li Kun, Xing Xiangchuan, Bao Huifang, Huang Nana, Zhu Guoqiang, Bai Xingwen, Sun Pu, Fu Yuanfang, Li Pinghua, Zhang Jing, Ma Xueqing, Li Dong, Liu Zaixin, Lu Zengjun
State Key Laboratory of Veterinary Etiological Biology, OIE/National Foot-and-Mouth Disease Reference Laboratory of China, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China.
Tianjin Weite Biological Medicine Co., Ltd., Tianjin 300301, China.
Vaccines (Basel). 2021 Apr 15;9(4):387. doi: 10.3390/vaccines9040387.
Foot-and-mouth disease (FMD) is a highly contagious disease and one of the most economically important diseases of livestock. Vaccination is an important measure to control FMD and selection of appropriate vaccine strains is crucial. The objective of this study was to select a vaccine candidate and to evaluate the potential of a blocking ELISA for detecting neutralizing antibodies (NA-ELISA) in vaccine strain selection. Binary ethylenimine inactivated vaccines, prepared from four representative circulating strains (FMDV O/Mya/98, SCGH/CHA/2016, O/Tibet/99, and O/XJ/CHA/2017) belonging to four lineages within three different topotypes of FMD virus (FMDV) serotype O in China, were used to vaccinate cattle (12-13 animals for each strain), sheep (12-13 animals for each strain), and pigs (10 animals for each strain). The results of immunogenicity comparison showed that O/XJ/CHA/2017 exhibited the highest immunogenicity among the four strains in pigs, cattle, and sheep both by NA-ELISA and virus neutralizing test (VNT). Cross-neutralization analysis indicated that O/XJ/CHA/2017 displayed broad antigen spectrum and was antigenically matched with other three representative strains both by NA-ELISA and VNT. In addition, A significant correlation ( < 0.0001) was observed between the NA-ELISA titers and the VNT titers for four representative strains. The results showed that O/XJ/CHA/2017 was a promising vaccine strain candidate and NA-ELISA was comparable to VNT in neutralizing antibodies detection and could be used as the reference test system for vaccine strain selection.
口蹄疫（FMD）是一种高度传染性疾病，也是家畜中经济上最重要的疾病之一。疫苗接种是控制口蹄疫的重要措施，选择合适的疫苗毒株至关重要。本研究的目的是筛选一种候选疫苗，并评估阻断ELISA法（NA-ELISA）在疫苗毒株筛选中检测中和抗体的潜力。用中国O型口蹄疫病毒（FMDV）三种不同拓扑型内四个谱系的四种代表性流行毒株（FMDV O/Mya/98、SCGH/CHA/2016、O/Tibet/99和O/XJ/CHA/2017）制备的双乙烯亚胺灭活疫苗，分别用于接种牛（每个毒株12 - 13头）、羊（每个毒株12 - 13只）和猪（每个毒株10头）。免疫原性比较结果表明，无论是通过NA-ELISA还是病毒中和试验（VNT），O/XJ/CHA/2017在猪、牛和羊的四种毒株中免疫原性最高。交叉中和分析表明，O/XJ/CHA/2017具有广泛的抗原谱，并且通过NA-ELISA和VNT与其他三种代表性毒株在抗原性上匹配。此外，观察到四种代表性毒株的NA-ELISA效价和VNT效价之间存在显著相关性（<0.0001）。结果表明，O/XJ/CHA/2017是一种有前景的候选疫苗毒株，NA-ELISA在中和抗体检测方面与VNT相当，可作为疫苗毒株筛选的参考检测系统。
