Roghayeh Teimourpour - Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
Hadi peeridogaheh - Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
Amir Teimourpour - Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical science, Tehran, Iran
Mohsen Arzanlou - Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
Zahra Meshkat - Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

Objective(s): Tuberculosis (TB) has still remained a global health issue. One third of the world's population is infected with tuberculosis and the current BCG vaccine has low efficiency; hence, it is necessary to develop a new vaccine against TB. The aim of the current study was to evaluate the efficiency of a novel DNA vaccine encoding Mtb۳۲C-HBHA antigen in inducing specific immune responses against Mycobacterium tuberculosis. Materials and Methods: A DNA plasmid vaccine expressing Mtb۳۲C-HBHA fusion protein was constructed and its ability in protein expression was examined by RT-PCR and Western blot methods. Female BALB/c mice were vaccinated with ۱۰۰ μg of purified recombinant vector in an attempt to assess its immunogenicity and protective efficacy. Further, the cytokines, IFN-γ, IL-۱۲, IL-۴, IL-۱۰, and TGF-β were assessed. Results: The levels of all the studied cytokines were significantly increased (P<۰.۰۵) compared with the control group. IFN-γ production in the group receiving DNA vaccine plus BCG was increased compared with those receiving only DNA vaccine or BCG (P<۰.۰۰۱). Conclusion: The immunogenicity of the new chimeric DNA vaccine was confirmed alone and in combination with BCG. Based on the results of the current study, the constructed DNA vaccine induced the expression of Mtb۳۲C-HBHA fusion protein efficiently in vitro. Furthermore, high levels of the specific cytokines were induced in mice. By using this DNA vaccine as a booster after BCG, higher amounts of IFN-γ will be produced.

BCG, DNA, Mycobacterium tuberculosis, PCR, Plasmid