title: Immunogenic Burkholderia pseudomallei outer membrane proteins as potential candidate vaccine targets.
abstract: BACKGROUND
  Burkholderia pseudomallei is the causative agent of melioidosis, a disease of significant morbidity and mortality in both human and animals in endemic areas. There is no vaccine towards the bacterium available in the market, and the efficacy of many of the bacterium's surface and secreted proteins are currently being evaluated as vaccine candidates.
  
  
  RESULTS
  With the availability of the B. pseudomallei whole genome sequence, we undertook to identify genes encoding the known immunogenic outer membrane protein A (OmpA). Twelve OmpA domains were identified and ORFs containing these domains were fully annotated. Of the 12 ORFs, two of these OmpAs, Omp3 and Omp7, were successfully cloned, expressed as soluble protein and purified. Both proteins were recognised by antibodies in melioidosis patients' sera by Western blot analysis. Purified soluble fractions of Omp3 and Omp7 were assessed for their ability to protect BALB/c mice against B. pseudomallei infection. Mice were immunised with either Omp3 or Omp7, subsequently challenged with 1x10(6) colony forming units (cfu) of B. pseudomallei via the intraperitoneal route, and examined daily for 21 days post-challenge. This pilot study has demonstrated that whilst all control unimmunised mice died by day 9 post-challenge, two mice (out of 4) from both immunised groups survived beyond 21 days post-infection.
  
  
  CONCLUSIONS
  We have demonstrated that B. pseudomallei OmpA proteins are immunogenic in mice as well as melioidosis patients and should be further assessed as potential vaccine candidates against B. pseudomallei infection.
authors: Malaysia Genome Institute, UKM-MTDC Smart Technology Centre, Bangi, Selangor, Malaysia.
authors: Yuka
authors: Y
authors: Hara
authors: Rahmah
authors: R
authors: Mohamed
authors: Sheila
authors: S
authors: Nathan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D001428:Bacterial Vaccines; D015153:Blotting, Western; D016957:Burkholderia pseudomallei / Q000235:genetics / Q000276:immunology*; D016680:Genome, Bacterial; D006801:Humans; D008554:Melioidosis / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010865:Pilot Projects; D017386:Sequence Homology, Amino Acid
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines