Abstract
Foot-and-mouth disease (FMD) is a notifiable contagious disease of cloven-hoofed mammals. A high potency vaccine that stimulates the host immune response is the foremost strategy used to prevent disease persistence in endemic regions. FMD vaccines comprise inactivated virus antigens whose immunogenicity is potentiated by immunogenic adjuvants. Oil-based adjuvants have clear advantages over traditional adjuvant vaccines; however, there is potential to develop novel adjuvants to increase the potency of FMD vaccines. Thus, we aimed to evaluate the efficacy of a novel water-in-oil emulsion, called CAvant®SOE, as a novel vaccine adjuvant for use with inactivated FMD vaccines. In this study, we found that inactivated A22 Iraq virus plus CAvant®SOE (iA22 Iraq-CAvant®SOE) induced effective antigen-specific humoral (IgG, IgG1, and IgG2a) and cell-mediated immune responses (IFN-γ and IL-4) in mice. Immunization of pigs with a single dose of iA22 Iraq-CAvant®SOE also elicited effective protection, with no detectable clinical symptoms against challenge with heterologous A/SKR/GP/2018 FMDV. Levels of protection are strongly in line with vaccine-induced neutralizing antibody titers. Collectively, these results indicate that CAvant®SOE-adjuvanted vaccine is a promising candidate for control of FMD in pigs.
Highlights
Foot-and-mouth disease (FMD) is a highly contagious, economically important transboundary animal disease of cloven-hoofed animals such as cattle, swine, goats, and sheep [1]
Clinical protection against FMD correlates with humoral immunity, which is used as an indirect tool to measure the potency of FMD vaccines based on serological responses after vaccination [37]
A similar pattern of results was observed in the FMD virus (FMDV) type A structural protein (SP) Enzyme-Linked Immunosorbent Assay (ELISA) assay, in which mice immunized with CAvant®SOE-adjuvanted A22 Iraq achieved seropositivity concerning mean present inhibition (PI > 50) antibody titers (Figure 1C)
Summary
Foot-and-mouth disease (FMD) is a highly contagious, economically important transboundary animal disease of cloven-hoofed animals such as cattle, swine, goats, and sheep [1]. FMD causes severe economic losses due to loss of productivity, costly eradication policies, and impediments to international trade [3,4]. Inactivated antigens concentrated to six PD50 or above have been used as an emergency vaccine to control outbreaks in FMD-free countries; this formulation was effective as early as 4 days post-vaccination (dpv) [10,11,12]. The Food and Agriculture Organization and the OIE both recommended strict guidelines for quality control testing of inactivated FMD antigen production; these guidelines pertain to identification, sterilization, safety profiles, potency, efficacy, and detection of FMDV non-structural proteins [13]. Inactivated virus antigen alone is poorly immunogenic; inactivated FMD vaccines are regularly formulated with an effective adjuvant to increase immunogenicity while at the same time reducing the antigen payload [14,15,16]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
