Dataset Information

Immunogenicity evaluation of plasmids encoding Brucella melitensis Omp25 and Omp31 antigens in BALB/c mice.

ABSTRACT:

Objectives

Vaccination is one of the most effective means to protect humans and animals against brucellosis. Live attenuated Brucella vaccines are considered effective in animals but they may be potentially infectious to humans, so it is vital to improve the immunoprotective effects and safety of vaccines against Brucella. This study was designed to evaluate the immunogenicity of DNA vaccines encoding B. melitensis outer membrane proteins (Omp25 and Omp31) against B. melitensis Rev1 in a mouse model.

Materials and methods

For this propose, Omp25 and Omp31 genes were cloned (individually and together) into the eukaryotic expression vector pcDNA3.1/Hygro (+). Expressions of recombinant plasmids were confirmed by SDS-PAGE and Western blot analysis. Six groups of BALB/c mice (seven mice per group) were intramuscularly injected with three recombinant constructs, native pcDNA3.1/Hygro (+) and phosphate-buffered saline (PBS) as controls and subcutaneous injection of attenuated live vaccine Rev1.

Results

Results indicated that DNA vaccine immunized BALB/c mice had a dominant immunoglobulin G response and elicited a T-cell-proliferative response and induced significant levels of interferon gamma (INF-γ) compared to the control groups.

Conclusion

Collectively, these finding suggested that the pcDNA3.1/Hygro DNA vaccines encoding Omp25 and Omp31 genes and divalent plasmid were able to induce both humoral and cellular immunity, and had the potential to be a vaccine candidate for prevention of B. melitensis infections.

SUBMITTER: Shojaei M

PROVIDER: S-EPMC6272067 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Publications

Immunogenicity evaluation of plasmids encoding <i>Brucella melitensis</i> Omp25 and Omp31 antigens in BALB/c mice.

Shojaei Moslem M Tahmoorespur Mojtaba M Soltani Mahdi M Sekhavati Mohammad Hadi MH

Iranian journal of basic medical sciences 20180901 9

<h4>Objectives</h4>Vaccination is one of the most effective means to protect humans and animals against brucellosis. Live attenuated Brucella vaccines are considered effective in animals but they may be potentially infectious to humans, so it is vital to improve the immunoprotective effects and safety of vaccines against Brucella. This study was designed to evaluate the immunogenicity of DNA vaccines encoding <i>B. melitensis</i> outer membrane proteins (Omp25 and Omp31) against <i>B. melitensis ...[more]

PMID: 30524697

Similar Datasets

Project description:BACKGROUND:Designing a potent recombinant vaccine, using the appropriate subunits with the greatest effect on stimulating the immune system, especially in the case of intracellular pathogens such as gram negative Brucella Melitensis bacteria, is of great importance. In this study, three repeats of 27 amino acids of the immunogenic epitope derived from OMP31 antigen (3E) from the Brucella melitensis, in a protective manner against Brucellosis have been used. To fortify the delivery system of recombinant antigens, IL-2 cytokine as a molecular adjuvant was fused to recombinant constructs. Recombinant proteins were evaluated for immunological studies in a mouse model (BALB/c). RESULTS:The results showed that all recombinant proteins could stimulate the immune system to produce Th1 cytokines and antibodies in compare to the negative control treatments. 3E-IL2 and then OMP31-IL2 proteins stimulated higher levels of IFN-γ and IL-2 compared to the other treatments (p < 0.05). Also, the results indicated that experimental treatments produced a higher level of IgG2a isotype than IgG1 isotype. In addition, the findings of the experiment showed that the presence of chemical adjuvant (IFA) along with molecular adjuvant can play a significant role in stimulating the immune system. After determining the potency of recombinant structures, their efficacy in stimulating the immune system were also evaluated. B. melitensis M16 strain was used to challenge 30 days after last immunization. The microbial load of the splenocyte in the treatments receiving chimeric proteins were significantly lower. Also, Wright serological test confirmed that these treatments had the lowest agglutination rate, as well as the positive treatment, while in the negative treatments in excess of blood serum dilutions, agglutination rate were more than 2 + . CONCLUSIONS:3E-IL2 treatment showed the best performance compared to other recombinant proteins and could be considered as the suitable candidate for further research on the production of recombinant vaccine against Brucella.