Numbers of gamma interferon (IFN-gamma)-producing cells reactive to ESAT-6 antigen were increased in recent converters to purified protein derivative positivity and in tuberculosis patients but not in unvaccinated or Mycobacterium bovis BCG-vaccinated healthy donors. ESAT-6-reactive IFN-gamma-producing cells in recent converters and tuberculosis patients recognized similar synthetic peptides. T...

BACKGROUND One of the most widely used methods to detect tuberculosis (TB) infection is the tuberculin skin test (TST). The completion of Mycobacterium tuberculosis (M. tuberculosis) genome sequence has led to identification of several antigens that can be utilized for accurate diagnosis and control of TB. The aim of this study was to purify the recombinant M. tuberculosis antigens for the eval...

The ESX systems from Mycobacterium tuberculosis are responsible for the secretion of highly immunogenic proteins of key importance for bacterial survival and growth. The two prototypic proteins, ESAT-6 (EsxA from ESX-1) and TB10.4 (EsxH from ESX-3) share a lot of characteristics regarding genome organization, size, antigenic properties, and vaccine potential but the two molecules clearly have v...

The 6-kDa early secreted antigenic target ESAT-6 and the 10-kDa culture filtrate protein CFP-10 of Mycobacterium tuberculosis are secreted by the ESX-1 system into the host cell and thereby contribute to pathogenicity. Although different studies performed at the organismal and cellular levels have helped to explain ESX-1-associated phenomena, not much is known about how ESAT-6 and CFP-10 contri...

OBJECTIVES Tuberculosis (TB) is still one of the problematic infectious diseases in developing countries, especially in Iran. In the present study, we applied ribosome display technique to select single chain variable fragments (scFvs) specific for the 6-kDa early secretory antigenic target (ESAT-6) antigen of Mycobacterium tuberculosis from a mouse scFv library. MATERIALS AND METHODS The gen...

ESAT-6 is an important T-cell antigen recognized by protective T cells in animal models of infection with Mycobacterium tuberculosis. In an enzyme-linked immunosorbent assay (ELISA) with overlapping peptides spanning the sequence of ESAT-6, monoclonal antibody HYB76-8 reacted with two peptides in the N-terminal region of the molecule. Assays with synthetic truncated peptides allowed a precise m...

CD8 T cells play a critical role in control of chronic viral infections; however, the role of these cells in containing persistent bacterial infections, such as those caused by Mycobacterium tuberculosis (Mtb), is less clear. We assessed the phenotype and functional capacity of CD8 T cells specific for the immunodominant Mtb antigens CFP-10 and ESAT-6, in patients with pulmonary tuberculosis (T...

The limited efficacy of the BCG vaccine against tuberculosis is partly due to the missing expression of immunogenic proteins. We analyzed whether the addition to BCG of ESAT-6 and HspX, two Mycobacterium tuberculosis (Mtb) antigens, could enhance its capacity to activate human dendritic cells (DCs). BCG showed a weak ability to induce DC maturation, cytokine release, and CD4(+) lymphocytes and ...