Key result
A prime-boost vaccination strategy using an rSFV-FMDV vector followed by FMDV empty capsids elicited a strong anti-FMDV antibody response, protected cattle against clinical disease, and prevented detectable viremia post-challenge.
A prime-boost vaccination strategy using rSFV-FMDV vectors and empty capsids effectively protects cattle against foot-and-mouth disease, offering a safer alternative to traditional inactivated virus vaccines.
Foot-and-mouth disease (FMD) remains one of the most economically important infectious diseases of production animals globally. Vaccination can successfully control this disease, however, current vaccines are imperfect. They are made using chemically inactivated FMD virus (FMDV) that is produced in large-scale mammalian cell culture under high containment conditions. Here, we have expressed the FMDV capsid protein precursor (P1-2A) of strain O1 Manisa alone or with the FMDV 3C protease (3Cpro) using a "single cycle" packaged alphavirus self-replicating RNA based on Semliki Forest virus (SFV). When the FMDV P1-2A was expressed with 3Cpro then processing of the FMDV capsid precursor protein is observed within cells and the proteins assemble into empty capsid particles. The products interact with anti-FMDV antibodies in an ELISA and bind to the integrin αvβ6 (a cellular receptor for FMDV). In cattle vaccinated with these rSFV-FMDV vectors alone, anti-FMDV antibodies were elicited but the immune response was insufficient to give protection against FMDV challenge. However, the prior vaccination with these vectors resulted in a much stronger immune response against FMDV post-challenge and the viremia observed was decreased in level and duration. In subsequent experiments, cattle were sequentially vaccinated with a rSFV-FMDV followed by recombinant FMDV empty capsid particles, or vice versa, prior to challenge. Animals given a primary vaccination with the rSFV-FMDV vector and then boosted with FMDV empty capsids showed a strong anti-FMDV antibody response prior to challenge, they were protected against disease and no FMDV RNA was detected in their sera post-challenge. Initial inoculation with empty capsids followed by the rSFV-FMDV was much less effective at combating the FMDV challenge and a large post-challenge boost to the level of anti-FMDV antibodies was observed. This prime-boost system, using reagents that can be generated outside of high-containment facilities, offers significant advantages to achieve control of FMD by vaccination.
No takes yet. Share an insight, caveat, or question.
Gullberg et al. (2016) studied Foot-and-Mouth Disease (n=30). Prime-boost vaccination (rSFV-FMDV vector followed by FMDV empty capsids) vs. Unvaccinated controls, single vaccination, or reverse order vaccination was evaluated on Protection against clinical disease and viremia post-challenge. A prime-boost vaccination strategy using an rSFV-FMDV vector followed by FMDV empty capsids elicited a strong anti-FMDV antibody response, protected cattle against clinical disease, and prevented detectable viremia post-challenge.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: