Since a basic principle for selecting novel antigen candidates for designing a TB subunit vaccine is based on their ability to induce a protective Th1 response [16], our study also confirmed the value of Ag85A, Ag85B and ESAT-6 as potential vaccine candidates based upon specific T cell responses measured by IFN-γ and TNF-α production in all studied patients. This evidence concerns the gene IFNG and tuberculosis.