title: Recombinant heat shock protein 60 (Hsp60/GroEL) of Salmonella enterica serovar Typhi elicits cross-protection against multiple bacterial pathogens in mice.
abstract: Heat shock proteins (HSPs) or stress proteins are recognized as protective antigens against a wide range of bacterial diseases. Conservation of HSPs across different life forms also appears to contribute to the antigenicity of these proteins. Due to their high sequence homology, there exists an immunological cross-recognition between different bacterial species. In the present study, we evaluated the efficacy of recombinant GroEL of Salmonella enterica serovar Typhi as a vaccine candidate against various bacterial pathogens viz.; Shigella dysenteriae type I, Shigella flexneri, Shigella boydii, enteropathogenic Escherichia coli (EPEC), Klebsiella pneumoniae and Pseudomonas aeruginosa. In vitro serum bactericidal assay (SBA) with GroEL antisera showed 50-55% inhibition of cells of Shigella Spp., 65-75% of E. coli, 60-65% of K. pneumoniae, 45-50% of P. aeruginosa. In in vivo experiments, mice immunized with GroEL protein of S. Typhi showed 60-65% protection against S. flexneri, S. dysenteriae type I, S. boydii. Similarly 75-80% protection was observed against enteropathogenic E. coli, 70-80% against K. pneumoniae. 50% of mice survived the lethal infection against P. aeruginosa. Organ burden and histopathological studies also revealed significant reduction of bacterial infection. This study shows the cross-protective efficacy of recombinant GroEL of S. Typhi which could lead to the development of a single vaccine candidate protective against multiple bacterial pathogens.
authors.affiliation: Experimental Biology Division, Defence Institute of Physiology and Allied Sciences DIPAS, Lucknow Road, Timarpur, Delhi-110054, India.
authors.forename: S T S
authors.initials: ST
authors.lastname: Chitradevi
authors.forename: G
authors.initials: G
authors.lastname: Kaur
authors.forename: K
authors.initials: K
authors.lastname: Singh
authors.forename: R
authors.initials: R
authors.lastname: Sugadev
authors.forename: A
authors.initials: A
authors.lastname: Bansal
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001424:Bacterial Infections / Q000276:immunology / Q000382:microbiology* / Q000517:prevention & control*; D001428:Bacterial Vaccines / Q000737:chemistry / Q000276:immunology*; D018834:Chaperonin 60 / Q000276:immunology*; D056738:Cross Protection / Q000276:immunology*; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D012485:Salmonella typhi / Q000737:chemistry* / Q000276:immunology; D012760:Shigella / Q000276:immunology; D014611:Vaccination
chemical_list: D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D018834:Chaperonin 60