Protein nanoparticle-based vaccine candidate produced in Nicotiana benthamiana against non-typhoidal Salmonella enterica in poultry

Non-typhoidal Salmonella enterica serovars are enteric pathogens in humans that can be acquired from poultry products. Salmonella colonisation in poultry is an important cause of economic losses. Due to challenges in controlling Salmonella in poultry and the emergence of well-adapted, antibiotic-resistant serovars, there is a need for innovative control strategies, such as vaccines. In this work, plants were used to produce conserved antigenic epitopes of Salmonella FepA, an outer membrane protein involved in iron uptake, genetically fused in tandem to self-assembling lumazine synthase from Brucella spp. (BLS). The recombinant proteins were purified, characterized, and their immunogenicity was assessed in chickens. Results indicated that the recombinant proteins assemble into decameric particles. These proteins elicit antigen-specific antibodies in chickens that bind to the Salmonella’s cell surface. These results demonstrate that the candidate vaccine has the potential to control Salmonella colonization in poultry, helping prevent food chain contamination.