Immunogenicity of a DNA Vaccine Encoding Ag85a-Tb10.4 Antigens from Mycobacterium Tuberculosis

Document Type: Original Article

Authors

1 Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

2 Department of Epidemiology and Biostatistics, Tehran University of Medical Science, Tehran, Iran

3 Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran

Abstract

Background: Tuberculosis is a life threatening disease that is partially prevented by
BCG vaccine. Development of more effective vaccines is an urgent priority in TB
control. Ag85a and Tb10.4 are the members of culture filter protein (CFP) of M.
tuberculosis that have high immunogenicity. Objective: To analyze the
immunogenicity of Ag85a-Tb10.4 DNA vaccine by enzyme-linked immunosorbent
assay (ELISA). Methods: In this study a previously described plasmid DNA vaccine
encoding Ag85a-Tb10.4 was used to examine its capability in the stimulation of
immune responses in an animal model. Female BALB/c mice were vaccinated with 100
μg of purified recombinant vector intramuscularly 3 times at two-week intervals and the
levels of five cytokines including IFN-γ, IL-12, IL-4, IL-10 and TGF-β were measured.
Results: The levels of IFN-γ and IL-12 for the mice following immunization with
Ag85A-Tb10.4 was significantly greater than that of the BCG and control group
(p<0.05). However there was no significant difference in the levels of IL-4, IL-10 and
TGF-β between groups. Conclusion: IFN-γ and IL-12 Th1 cytokines increased
significantly in mice vaccinated with Ag85a-TB10.4 DNA vaccine in comparison to the
control and BCG groups. Our results may serve as groundwork for further research into
the prevention and treatment of tuberculosis.

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