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=6

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=<p><italic>Mycobacterium bovis</italic> bacillus Calmette-Guérin (BCG) is currently the only vaccine available for preventing tuberculosis (TB), however, BCG has varying success in 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. Our results indicated that the Ag85A protein was successfully overexpressed in rBCG::Ag85A, and the Ag85A peptide–MHC complexes on draining lymph node dendritic cells of C57BL/6 mice infected with rBCG::Ag85A 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 rBCG::Ag85A can enhance protection against <italic>Mycobacterium tuberculosis</italic> (<italic>M. tuberculosis</italic>) H37Rv infection compared to the BCG vaccine alone. Our results demonstrate the potential of rBCG::Ag85A as a candidate vaccine against TB.</p>