The role of passively transferred sera in the protection against aerogenous foot-and-mouth disease (FMD) virus infection in cattle was evaluated using vaccine-induced immune serum preparations obtained at 7 and 26 days post-vaccination (dpv). We showed that circulating antibodies were sufficient to prevent disease generalization after oronasal infection in animals passively transferred with 26-dpv serum but not with the 7-dpv serum. Conversely, conventional FMD vaccination provided clinical protection at 7 dpv, promoting fast and robust antibody responses upon challenge and even though antibody titers were similar to those found in animals passively immunized with 7-dpv serum. These results demonstrate that presence of antigen-specific antibodies is critical to prevent the dissemination of the virus within the animal. Conventional FMD vaccination additionally promoted the deployment of rapid, high titer and isotype-switched antibody responses at systemic and mucosal levels after infection, thus conferring protection even in the presence of low pre-challenge antibody titers.

使用疫苗接种后7天和26天获得的疫苗诱导的免疫血清制剂，评估了被动转移血清在预防牛源性口蹄疫（FMD）病毒感染中的作用。我们显示循环抗体足以预防口鼻感染后被动传播26-dpv血清而不是7-dpv血清的动物疾病泛滥。相反，常规的FMD疫苗接种可在7 dpv时提供临床保护，即使在感染7 dpv血清被动免疫动物后，其效价相似，也能在激发后促进快速而稳定的抗体反应。这些结果表明，抗原特异性抗体的存在对于防止病毒在动物体内的传播至关重要。