Immunologically cross reactive proteins for broadly protective Campylobacter chicken vaccines

Human Campylobacter disease caused by the foodborne pathogens, Campylobacter jejuni and Campylobacter coli, is a huge public health problem globally. The economic burden of this disease, which ranges from mild self-limiting diarrhea to devastating neurological complications, in the United States alone is estimated at more than USD 8 billion annually. Broiler chickens harbor these pathogens in their gastrointestinal tracts (GITs) without developing disease, and are primary reservoirs considered to be the principal source of human infection. Hence, efficacious vaccines for elimination of these pathogens from the GITs of broiler chickens will significantly reduce incidence of human Campylobacteriosis; however, despite an urgent need, currently there are no efficacious chicken Campylobacter vaccines commercially available. Thus far, progress toward development of efficacious Campylobacter chicken vaccines has been slow. This is because Campylobacter species that infect broiler chickens and have human disease causing potential are a very diverse group, which dictates that efficacious vaccines comprise multiple components, including proteins that are shared by the vast majority chicken Campylobacter strains/isolates with human disease causing potential (conserved proteins). Also, the lack of innovative discovery tools for identification of conserved pathogen proteins is another contributory factor, since such conserved proteins are "hidden" by the pathogen during natural infection to escape host defenses. PELS is one such innovative tool that has the ability to identify conserved pathogen proteins (antigens). This antigen discovery technology makes clever use of the response of a host infected with a pathogen to identify components (proteins) with potential for vaccines against the same pathogen. In this project, PELS will be applied in an innovative manner, and coupled with a suite of computer-based algorithms for identification of proteins that are shared by diverse Campylobacter chicken and human strains/isolates. It is expected that this study will result in a panel of conserved Campylobacter proteins, a subset of which is likely to have potential for development of broadly protective Campylobacter chicken vaccines. Future studies in broiler chickens will examine if these proteins can function as vaccines. Such vaccines are anticipated to reduce the public health burden, as well as significantly reduce health care costs currently expended toward management of human Campylobacteriosis in the United States.