AUTHOR=Xu Zheng Zhong , Chen Xiang , Hu Ting , Meng Chuang , Wang Xiao Bo , Rao Yan , Zhang Xiao Ming , Yin Yue Lan , Pan Zhi Ming , Jiao Xin An 

TITLE=Evaluation of Immunogenicity and Protective Efficacy Elicited by Mycobacterium bovis BCG Overexpressing Ag85A Protein against Mycobacterium tuberculosis Aerosol Infection

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=Volume 6 - 2016

YEAR=2016

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2016.00003

DOI=10.3389/fcimb.2016.00003

ISSN=2235-2988

ABSTRACT=Mycobacterium bovis bacillus Calmette-Guérin (BCG) is currently the only vaccine available against tuberculosis (TB), however, it has various levels of efficacy for preventing pulmonary TB. In this study, a recombinant BCG (rBCG::Ag85A) strain overexpressing the immunodominant Ag85A antigen was constructed, and its immunogenicity and protective efficacy were evaluated. The results showed that the Ag85A protein was successfully overexpressed in rBCG::Ag85A, the Ag85A peptide–MHC complexes on draining lymph node dendritic cells of C57BL/6 mice infected with rBCG were detectable 4 h post-infection. The C57BL/6 mice infected with this strain had stronger antigen-specific interferon-gamma (IFN-γ) responses and higher antibody titers than those immunized with BCG, and the protective experiments showed that the rBCG::Ag85A can provide higher but not significantly protective efficacy against Mycobacterium tuberculosis (M. tuberculosis) H37Rv infection compared with BCG vaccine. Therefore, our results demonstrated the potential of rBCG::Ag85A as a vaccine candidate against TB.