• Vaccine Name: Recombinant B. abortus RB51SOD
• Target Pathogen: Brucella spp.
• Target Disease: Brucellosis
• Vaccine Ontology ID: VO_0000720
• Type: Live attenuated B. abortus strain
• SodC from B. abortus strain 2308 gene engineering:
  • Type: Protein overexpression
  • Description: B. abortus Cu/Zn SOD is over-expressed in recombinant strain RB51SOD using the broad-range plasmid pBBR1MCS (Vemulapalli et al., 2000a).
  • Detailed Gene Information: Click Here.
• Preparation: The gene for B. abortus Cu/Zn SOD (sodC) along with its own promoter was initially obtained from a genomic library of B. abortus strain 2308, and later subcloned into pBBR1MCS, a broad-host-range plasmid. The resulting plasmid pBBSOD was transformed into E. coli DH5a, confirmed, purified, and then electroporated into B. abortus strain RB51. Strain RB51 containing the plasmid pBBSOD was designated RB51SOD (Vemulapalli et al., 2000a).
• Virulence: RB51SOD is not more virulent than RB51 (Vemulapalli et al., 2004).
• Storage: RB51SOD does not increase virulence compared to RB51.
• Description: RB51SOD is a recombinant strain of B. abortus cattle vaccine strain RB51. RB51SOD overexpresses B. abortus Cu/Zn superoxide dismutase (SOD). Overexpression of this enzyme significantly increases vaccine efficacy against strain 2308 challenge (Vemulapalli et al., 2004).

Mouse Response

• Host Strain: BALB/c mice
• Vaccination Protocol: RB51SOD was used to vaccinate mice with a dose of ~4 x 10^8 cfu per mouse.
• Persistence: The presence of the Cu/Zn SOD plasmid in strain RB51 does not alter its vaccine efficacy. Overexpression of SOD does not alter the attenuation characteristic of strain RB51 (Vemulapalli et al., 2000a).
• Vaccine Immune Response Type: VO_0003068
• Side Effects: None observed.
• Efficacy: Recombinant strain RB51SOD in mice induces better protection against virulent B. abortus infection compared to B. abortus vaccine strain RB51 (Vemulapalli et al., 2000a).
  
• Description: Mice vaccinated with RB51SOD, but not RB51, develop antibodies and cell-mediated immune responses to Cu/Zn SOD (Vemulapalli et al., 2000a).
  
• Host Ifng (Interferon gamma) response
  • Description: Mice vaccinated with strain RB51SOD developed a Th1 immune response to the CuZn SOD, indicated by specific induction of serum IgG2a antibodies, but not IgG1 antibodies. IFN-gamma , but not IL -4 is secreted by CuZn SOD-stimulated splenocytes (Vemulapalli et al., 2000a). The enhanced protective immunity conferred by strain RB51SOD my be attributed to the specific cell-mediated responses, especially IFN-gamma secretion (Vemulapalli et al., 2000a).
  • Detailed Gene Information: Click Here.