Exploiting the power of OMICS approaches to produce E. coli O157 vaccines

Enterohemorrhagic Escherichia coli (EHEC) strains are well-documented human pathogens and causative agents of diarrheal episodes and hemorrhagic colitis. The serotype O157:H7 is highly virulent and responsible for both outbreaks and sporadic cases of diarrhea. Because antibiotic treatment is contraindicated against this pathogen, development of a human vaccine could be an effective intervention in public health. In our recent Infection and Immunity paper, we applied integrated approaches of in silico genome wide search combined with bioinformatics tools to identify and test O157 vaccine candidates for their protective effect on a murine model of gastrointestinal infection. Using genomic/immunoinformatic approaches that are further described here, we categorized vaccine candidates as high, medium, and low priorities, and demonstrate that some high priority candidates were able to significantly induce Th2 cytokines and reduce EHEC colonization. Using the STRING database, we have recently evaluated the vaccine candidates and predict functional protein interactions, determining whether correlations exist for the development of a multi-subunit vaccine, targeting different pathways against EHEC O157:H7. The overall approach is designed to screen potential vaccine candidates against EHEC; however, the methodology can be quickly applied to many other intestinal pathogens.