Enhanced anti-tuberculosis immunity by a TAT-Ag85B protein vaccine in a murine tuberculosis model

Background: The development of more effective anti-tuberculosis vaccines would contribute to the control of the global problem of infection with Mycobacterium tuberculosis (MTB). Recently, increasing evidences showed that HIV-Tat protein transduction domain is implicated in promotion of vaccines by inducing cellular immuno-response. However, it is rare known about the role of TAT in vaccines against MTB. Methods: In this study, we expressed recombinant protein-fused Ag85B with TAT (TAT-Ag85B) which was used as a vaccine to inoculate mice infected with MTB. Results: As s result, both IgG2a in serum and IFN-gamma or TNF alpha produced by spleen cells were all increased significantly in the mice inoculated by TAT-Ag85B. Furthermore, consistently, TAT-Ag85B inoculation significantly reduced MTB loads both in lung and spleen. Conclusions: These findings demonstrate that a novel protein vaccine of TAT-Ag85B enhances immune response both in humoral and cellular immunity, and contributes to protective efficacy against MTB.