Institute of Virology and Technical Innovations, INTA-CONICET, Nicolás Repetto y Los Reseros S/N Hurlingham, 1686 Buenos Aires, Argentina.
Institute of Diagnostic Virology, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, Suedufer 10, 17493 Greifswald-Insel Riems, Germany.
Vaccine. 2024 Nov 14;42(25):126066. doi: 10.1016/j.vaccine.2024.06.033. Epub 2024 Jun 14.
This study aims to analyze if the results from different serological assays, used alone or combined, could match the outcome of challenge infection with foot-and-mouth disease virus (FMDV) after vaccination in cattle. Day-of-challenge sera from animals that had been vaccinated 21 days before with monovalent formulations containing inactivated A Iran 96 or A Iran 99 virus strains were used. Challenge and serology were performed with A22 Iraq strain. IgG1 titers and total-IgG avidity indexes were significantly higher in protected animals (p < 0.01) while IgG2-titers were not related to protection (p > 0.05). An IgG1 avidity ELISA was developed to analyze in one step, IgG1 levels and avidity. This assay estimated protection with 96 % accuracy. A strong agreement with challenge results was achieved (K = 0.85), suggesting a role of high-affinity IgG1 in protection against FMDV. These results support the assessment of the single dilution IgG1-Avidity ELISA to predict cross-protection in FMDV-vaccinated cattle.
本研究旨在分析单独或组合使用不同血清学检测方法的结果是否能与牛接种疫苗后口蹄疫病毒（FMDV）攻毒感染的结果相匹配。在接种疫苗 21 天后，使用含有灭活 A 伊朗 96 或 A 伊朗 99 病毒株的单价制剂对动物进行攻毒和血清学检测。攻毒和血清学检测使用 A22 伊拉克株进行。在受保护的动物中，IgG1 滴度和总 IgG 亲和力指数显著更高（p<0.01），而 IgG2 滴度与保护无关（p>0.05）。开发了一种 IgG1 亲和力 ELISA 来一步分析 IgG1 水平和亲和力。该检测方法以 96%的准确率估计了保护率。与攻毒结果具有很强的一致性（K=0.85），这表明高亲和力 IgG1 在预防 FMDV 中的作用。这些结果支持评估单稀释 IgG1-亲和力 ELISA 以预测 FMDV 接种牛的交叉保护。
