• Vaccine Name: P1-HspB (fusion of protein 1 and heat-shock protein B)
• Target Pathogen: Coxiella burnetii
• Target Disease: Q fever
• Vaccine Ontology ID: VO_0004133
• Type: Subunit vaccine
• p1 gene engineering:
  • Type: Recombinant protein preparation
  • Description: The primers were synthesized and the target DNA fragments were amplified by PCR from C. burnetii genomic DNA. The mixture used during amplification consisted of 0.3 M primer, 200 M deoxynucleoside triphosphate, and 0.6 U of Taq polymerase (Li et al., 2005). See preparation below for more information.
  • Detailed Gene Information: Click Here.
• htpB gene engineering:
  • Type: Recombinant protein preparation
  • Description: The primers were synthesized and the target DNA fragments were amplified by PCR from C. burnetii genomic DNA. The mixture used during amplification consisted of 0.3 M primer, 200 M deoxynucleoside triphosphate, and 0.6 U of Taq polymerase (Li et al., 2005). See preparation below for more information.
  • Detailed Gene Information: Click Here.
• Adjuvant:
  • Adjuvant name:
  • VO adjuvant ID: VO_0000139
• Adjuvant:
  • Adjuvant name:
  • VO adjuvant ID: VO_0000142
• Preparation: Gene fragments encoding C. burnetii outer membrane protein 1 (P1) and heat-shock protein B (HspB) are amplified by PCR from genomic DNA extracted from C. burnetii. The amplified p1 and hspB gene fragments are purified and digested with DNA endonuclease pairs BamHI/ScaI and SacI/PstI, respectively. The genes are then ligated with pQE30 (digested with homologous enzyme pair) with T4 ligase, resulting in recombinant expression plasmids pQE30/p1 and pQE30/hspB. Plasmid pQE30/p1-hspB is constructed by ligating hspB of pQE30/hspB with p1 fragment from pQE30/p1. E.coli M15 cells are then transformed with the ligation mixtures and screened on medium containing ampicillin and kanamycin. The E. coli cells were propagated in LB medium and induced by IPTG. The resulting recombinant proteins were purified by affinity chromatography with nickel-nitrilotriacetic resin (Li et al., 2005).

Mouse Response

• Host Strain: BALB/c
• Vaccination Protocol: Mice (six to eight weeks old) were immunized subcutaneously with 30 μg of purified P1, HspB, P1-HspB, or whole-cell antigen with Freund's complete adjuvant. After four weeks, the mice were then immunized intraperitoneally twice every two weeks with 15 μg of homologous antigen with Freund's incomplete adjuvant (Li et al., 2005).
• Immune Response: HspB was found to be efficient in eliciting humoral immunoresponses while P1 was found to be efficient in eliciting cell-mediated immunoresponses. There was higher antibody titer for HspB-ummunized mice than that for P1-immunized mice.
• Challenge Protocol: Eight weeks and ten days from after initial immunization, each group of mice was challenged with10-fold 50% infection dose of C. burnetii. After seven days, mice's spleens were removed and evaluated.
  (Li et al., 2005).
• Efficacy: P1-HspB fusion protein provided a better protection against C. burnetii than that offered by P1 or HspB alone (Li et al., 2005).