Ubiquitin and ESAT6 antigen fusion gene DNA vaccine induced stronger cellular immune response in mice / 第二军医大学学报

ABSTRACT

Objective: To construct Mycobacterium tuberculosis ESAT6 (pE) antigen DNA vaccine and ubiquitin-ESAT6 fusion gene (pUE) DNA vaccine. Methods: The constructed DNA vaccines were intramuscularly inoculated into female BALB/c mice separately. The serum antibodies (including IgG, IgG1, and IgG2a), Cytokines (IFN-γ and IL-4), and cytotoxic T lymphocytes response were detected in the immunized mice. Results: Mice in pE group had a higher serum level of IgG (P< 0.01) and a lower value of IgG2a /IgG1 ([2.28±0.40] vs [3.87±0.60],P<0.05) than mice in pUE group. Besides, mice in pUE group secreted more IFN-γ than those in pE group (P<0.01), but secreted less IL-4 (P<0.01). Furthermore, pUE enhanced the activity of CTL. The results showed that pUE DNA vaccine induced weaker humoral immune response, but stronger cellular immune responses compared to pE DNA vaccine. Conclusion: The pUE DNA vaccine constructed in this study sheds new lights on the prophylactic and therapy of tuberculosis.