Immunogenic Consideration of a Designed Polypeptide Against Brucellosis Compared to RB51: An In Vivo Study.

Background: Brucellosis in livestock and its transmission to humans through the consumption of contaminated dairy products is an important issue. The introduction of new approaches using immunogenic proteins against and diagnosing brucellosis is a serious issue in human health. Methods: Brucella abortus contains five proteins including: MOXR family ATPase-α2, T9SS C-terminal target domain-containing protein, Cobyric acid synthase, Hypothetical protein, and VirB11 type IV Secretion protein, which were considered and the designed recombinant polypeptide was produced and evaluated. The pure recombinant protein ABOR with 549aa in combination with chitin as an adjuvant was injected subcutaneously into guinea pigs to evaluate their immunity responses. Results: The results indicated that the ABOR recombinant protein induced Th1 immunity with high levels of specific IgG (IgG2a) as well as Interferon-γ (IFN-γ), Interleukin- 2 (IL-2), IL-12, and Tumor Necrosis Factor-alpha (TNF-α), compared to the control group. Th1/Th2 ratio analysis demonstrated the efficacy of ABOR protein combined with chitin in stimulating cellular immunity in the animals. Conclusion: Designed recombinant polypeptide combined with chitin showed ability for induction of cellular and humoral immunity an guinea pigs compared to RB51 vaccine. [ABSTRACT FROM AUTHOR]