Tuberculosis (TB), caused by Mycobacterium tuberculosis (M tuberculosis), is a worldwide public health problem and has infected humans for thousands of years.The conventional anti-TB vaccine,Mycobacterium bovis bacille Calmette-Guérin (BCG), has been widely used to prevent TB since 1921.However, the protective efficacy of BCG has shown variable effects against adult pulmonary TB in different trials even though it continues to be used to prevent meningitis and phthisis miliaris in children in many countries.Because of the emergence of multi-drug resistant M tuberculosis strains and human immunodeficiency virus infection as well as the lack of success of the TB vaccine, there have been ongoing efforts to develop more effective vaccines using the different strategies to fight against TB.The goal of this study was to evaluate the protective efficacy of cationic nanoparticle-based DNA vaccine expressing antigen 85A (Ag85A) and 6 kDa early secretory antigen target (ESAT-6) of M tuberculosis as well as cytokine interleukin (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 increased in the protective efficacy against M tuberculosis infection in the immunized mice.We concluded that the nanoparticle-based DNA vaccine induced a strong immune responses and markedly inhibited the growth of the M tuberculosis in the mice.These findings highlighted the potential utility of Fe3O4-Glu-PEI nanoparticles co-capsulated with the DNA vaccine as a prophylactic vaccine in the M.tuberculosis infected mouse model.