Surface-accessible proteins protect mice against pneumococcal disease.

2004 JUL 7 - (NewsRx.com & NewsRx.net) -- Immunization with conserved surface-accessible proteins protected mice against pneumococcal disease.

"The development of a vaccine against Streptococcus pneumoniae has been complicated by the existence of at least 90 antigenically distinct capsular serotypes. Common protein-based vaccines could represent the best strategy to prevent pneumococcal infections, regardless of serotype. In the present study, the immunoscreening of an S. pneumoniae genomic library allowed the identification of a novel immune protein target, BVH-3," scientists in Canada report.

"We demonstrate that immunization of mice with BVH-3 elicits protective immunity against experimental sepsis and pneumonia," said Josee Hamel and colleagues at the University of Quebec. "Sequence analysis revealed that the bvh-3 gene is highly conserved within the species. Since the BVH-3 protein shows homology at its amino-terminal end with other pneumococcal proteins, it was of interest to determine if protection was due to the homologous or to the protein-specific regions."

"Immunoprotection studies using recombinant BVH-3 and BVH-3-related protein fragments as antigens allowed the localization of surface-exposed and protective epitopes at the protein-specific carboxyl termini, thus establishing that BVH-3 is distinct from other ...