BALB/c mice were vaccinated with Brucella (B.) abortus recombinant protein L27 (50S ribosomal protein L27) cloned into a pMal vector system. L27 was induced, purified and injected intraperitoneally (IP). Mice were vaccinated on 0-, 15- and 35-day. Serum cytokines were evaluated on 36- and 49-day from first vaccination. Mice were intraperitoneally infected with 5×104 CFU of virulent B. abortus 544 on day-50 and sacrificed after two weeks from infection. Bacterial burden from the spleen was quantified and showed a 0.7- and 0.9-log reduction in vaccinated mice in comparison to PBS and MBP (maltose binding protein) groups respectively. Cytokines in the serum demonstrated increased interferon-gamma (IFN-γ) and other pro-inflammatory cytokines such as macrophage chemoattractant protein-1 (MCP-1) and interleukin 6 (IL-6). On the other hand, interleukin 10 (IL-10) was attenuated in the sera of vaccinated mice. This cytokine profile is indicative of a cell-mediated type of immune response which is favorable for the eradication of intracellular infections. The current study showed the potential of another B. abortus ribosomal protein in inducing protective immunity against B. abortus infection.

Abstract
INTRODUCTION
MATERIALS AND METHODS
    Growth of strains
    Expression and purification of recombinant L27
    Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and immunoblot analysis
    Mice vaccination and infection with B. abortus 544
    Serum cytokine evaluation
    Quantification of bacterial proliferation in the spleen
    Statistical analysis
RESULTS
    Determination and immunogenicity of target protein
    Protective effect of recombinant protein L27 in micechallenged with B. abortus infection
    Serum cytokine assessment
DISCUSSION
REFERENCES

• Lauren Togonon Arayan(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• Tran Xuan Ngoc Huy(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• Alisha Wehdnesday Bernardo Reyes(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• Vu Hai Son(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• WonGi Min(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• Hu Jang Lee(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• Suk Kim(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University) Corresponding Author.