Nanoparticle-based adjuvant for enhanced protective efficacy of DNA vaccine Ag85A-ESAT-6-IL-21 against Mycobacterium tuberculosis infection

The goal of this study was to evaluate the protective efficacy of a cationic nanoparticle-based DNA vaccine expressing antigen 85A (Ag85A) and 6-kDa early secretory antigen target (ESAT-6) of Mycobacterium tuberculosis as well as cytokine interleukin-21 (IL-21) against M. tuberculosis infection. The results of this indicated that the anti–M. tuberculosis immune responses were induced in mice that had received the different DNA vaccines. More importantly, compared with using DNA vaccine Ag85A-ESAT-6-IL-21 alone, the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21 showed a statistically significant increase in the protective efficacy against M. tuberculosis infection in the immunized mice. We concluded that the nanoparticle-based DNA vaccine induced a strong immune response and markedly inhibited the growth of the M. tuberculosis in the mice. These findings highlighted the potential utility of Fe3O4-Glu-polyethyleneimine nanoparticles encapsulated with the DNA vaccine as a prophylactic vaccine in the M. tuberculosis–infected mouse model.From the Clinical EditorThis study emphasizes the potential utility of Fe3O4-Glu-polyethyleneimine nanoparticles encapsulated with DNA vaccine against TB as a prophylactic vaccine. The authors demonstrated a strong immune response and marked growth inhibition of mycobacterium tuberculosis in the mice.

Graphical AbstractIn this study, we developed the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21, which effectively transported DNA vaccine into cells. The IL-21 acted as an immunoadjuvant, the Ag85A-ESAT-6 fusion protein acted as target antigens, and the nano-Fe3O4-Glu nanoparticles served as the vaccine delivery system, inducing a powerful immune response and protection against M. tuberculosis challenge in a mouse model, compared with the DNA vaccine Ag85A-ESAT-6-IL-21 alone. Our findings show that the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21 enhances immune prophylactic efficacy to protect against M. tuberculosis infection.Figure optionsDownload high-quality image (307 K)Download as PowerPoint slide