• Vaccine Name: Brucella abortus L7/L12 ribosomal protein subunit vaccine
• Target Pathogen: Brucella spp.
• Target Disease: Brucellosis
• Vaccine Ontology ID: VO_0009096
• Type: Subunit vaccine
• Status: Research
• Host Species for Licensed Use: Cattle
• Host Species as Laboratory Animal Model: Mus musculus (BALB/c mice); Bos taurus peripheral blood mononuclear cells; Escherichia coli DH5 alpha; Mus musculus
• Antigen: L7/L12 ribosomal protein
• Adjuvant: PLGA (poly lactic-co-glycolic acid) naparticles
• Preparation: Recombinant L7/L12 ribosomal protein (Oliveira et al, 1994)
  Recombinant L7/L12 fusion protein purified by affinity chromatography. (Oliveira et al, 1994a)
  PLGA (85:15) biodegradable and biocompatible polymer nanoparticles entrapping recombinant L7/L12 protein. (Singh et al, 2015a)
• Description: Ribosomal preparations have been used as vaccines against several pathogens including B. abortus, conferring a high degree of protection. Efficacy: Not directly reported; inferred protection based on induction of Th1 response. Immune response: Induced antigen-specific proliferation of CD4+ T cells with a Th1 cytokine profile characterized by IL-2 and IFN-gamma transcripts and secretion of IFN-gamma, but not IL-4. (Oliveira et al, 1994)
  The Brucella abortus L7/L12 ribosomal gene was amplified and expressed as a fusion protein in E. coli, purified, and confirmed by Western blot. Immune response: Recombinant L7/L12 protein induced proliferation of T lymphocytes, with an increased percentage of CD4+ T cells compared to control cultures. (Oliveira et al, 1994a)
  The study explores the immunogenic potential of PLGA (poly lactic-co-glycolic acid) nanoparticles entrapping rL7/L12 protein, an immunodominant antigen of Brucella abortus, as a vaccine candidate. Efficacy: Significant reduction in splenic bacterial load (log CFU) in vaccinated mice compared to controls after Brucella abortus 544 infection. Immune response: High IgG antibody titers with predominant IgG1 subclass indicating mixed Th1/Th2 response; strong Th1 cytokine (IFN-γ) production; increased lymphocyte proliferation indicating enhanced cellular immunity. (Singh et al, 2015a)

Mouse Response

• Vaccination Protocol: Immunization of mice followed by measurement of IgG antibody titers, IgG subclass analysis, Th1 cytokine (IFN-γ) production, lymphocyte proliferation assay, and enumeration of splenic CFU after. (Singh et al, 2015a)
• Immune Response: High IgG antibody titers with predominant IgG1 subclass indicating mixed Th1/Th2 response; strong Th1 cytokine (IFN-γ) production; increased lymphocyte proliferation indicating enhanced cellular immunity. (Singh et al, 2015a)
• Challenge Protocol: Immunization of mice followed by measurement of IgG antibody titers, IgG subclass analysis, Th1 cytokine (IFN-γ) production, lymphocyte proliferation assay, and enumeration of splenic CFU after challenge with Brucella abortus 544. (Singh et al, 2015a)
• Efficacy: Significant reduction in splenic bacterial load (log CFU) in vaccinated mice compared to controls after Brucella abortus 544 infection. (Singh et al, 2015a)
• Description: Immunization of mice followed by measurement of IgG antibody titers, IgG subclass analysis, Th1 cytokine (IFN-γ) production, lymphocyte proliferation assay, and enumeration of splenic CFU after challenge with Brucella abortus 544. (Singh et al, 2015a)