Implication of Broadly Neutralizing Bovine Monoclonal Antibodies in the Development of an Enzyme-Linked Immunosorbent Assay for Detecting Neutralizing Antibodies against Foot-and-mouth Disease Virus Serotype O

Vaccination with inactivated vaccines is still the main measure to control foot-and-mouth disease (FMD) in endemic areas, and the level of neutralizing antibody in vaccinated animals is directly related to their protection against virus challenge. Currently, neutralizing antibody is mainly detected using virus neutralization test (VNT) based on cell culture, which is laborious, time-consuming and requiring restrictive biocontainment facilities. In this study, two broadly neutralizing antibodies (bnAbs) E46 and F128 were successfully produced using single B cell isolation techniques from peripheral blood mononuclear cells (PBMCs) of bovine sequentially immunized with three topotypes of foot-and-mouth disease virus (FMDV) serotype O. Based on these bnAbs, a blocking ELISA for detecting neutralizing antibodies (NA-ELISA) against FMDV serotype O was developed. The specificity and sensitivity of the test were estimated as 99.21% and 100%, respectively. A significant correlation (P