Development a cross-protective subunit cocktail vaccine against diverse serotypes of Glaesserella parasuis infection in pigs

Glässer's disease caused by Glaesserella parasuis (GPS) is a severe disease that leads to huge economic losses in the swine industry worldwide due to the poor cross-protective efficacy of existing vaccines. In this study, a multi-antigen cocktail subunit vaccine against GPS infection was developed. By in-silico analyzing antigenicity and comparison of immunoprotective efficacy and induction of antibody titers in a murine model, the component of the cocktail vaccine was determined to be VacJ, PtsG and GAPDH, with Gel-01 as the optimal adjuvant. Immunization of the cocktail vaccine induced robust humoral and cellular immune responses both in vitro and in vivo . Importantly, the vaccine not only conferred effective cross-protection against lethal-dose of GPS4 and GPS5 infections in mice, but also demonstrated favorable immune protective efficacy against GPS infection in piglets. Moreover, their immune sera significantly inhibited the growth of GPS4 and GPS5. Overall, these results suggested that the subunit cocktail vaccine established in this study is a promising agent for the prevention and control of porcine Glässer's disease.