Prevention of pneumococcal disease in mice immunized with conserved surface-accessible proteins

Infect Immun. 2004 May;72(5):2659-70. doi: 10.1128/IAI.72.5.2659-2670.2004.

Abstract

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. We demonstrate that immunization of mice with BVH-3 elicits protective immunity against experimental sepsis and pneumonia. 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 previously reported protective protein antigens. Immunization with a chimeric protein comprising the carboxyl-terminal regions of BVH-3 and of a BVH-3-related protein improved the protection by targeting two surface pneumococcal components. Thus, BVH-3 and the chimeric protein hold strong promise as vaccine components to control pneumococcal disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Bacterial / biosynthesis
  • Antigens, Bacterial / genetics
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Conserved Sequence
  • Epitopes / genetics
  • Genes, Bacterial
  • Humans
  • Immunization
  • Immunization, Passive
  • Mice
  • Mice, Inbred BALB C
  • Molecular Sequence Data
  • Pneumococcal Infections / immunology*
  • Pneumococcal Infections / prevention & control*
  • Pneumococcal Vaccines / genetics
  • Pneumococcal Vaccines / immunology
  • Pneumococcal Vaccines / pharmacology
  • Pneumonia, Pneumococcal / immunology
  • Pneumonia, Pneumococcal / prevention & control
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Sepsis / immunology
  • Sepsis / prevention & control
  • Sequence Homology, Amino Acid
  • Serotyping
  • Streptococcus pneumoniae / classification
  • Streptococcus pneumoniae / genetics
  • Streptococcus pneumoniae / immunology*

Substances

  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Bacterial Proteins
  • Epitopes
  • Pneumococcal Vaccines
  • Recombinant Proteins

Associated data

  • GENBANK/AX343070
  • GENBANK/AX343072
  • GENBANK/AY278231
  • GENBANK/AY278232
  • GENBANK/AY278233
  • GENBANK/AY278234
  • GENBANK/AY278235
  • GENBANK/AY278236
  • GENBANK/AY278237
  • GENBANK/AY278238
  • GENBANK/AY278239
  • GENBANK/AY278240
  • GENBANK/AY278241
  • GENBANK/AY278242
  • GENBANK/AY278243
  • GENBANK/AY439016