Cellular immune responses to ESAT-6 discriminate between patients with pulmonary disease due to Mycobacterium avium complex and those with pulmonary disease due to Mycobacterium tuberculosis

Clin Diagn Lab Immunol. 1999 Jul;6(4):606-9.

Abstract

ESAT-6 (for 6-kDa early secreted antigenic target) is a secreted antigen found almost exclusively in organisms of the Mycobacterium tuberculosis complex. We compared in vitro gamma interferon (IFN-gamma) responses by peripheral blood mononuclear cells to this antigen in patients with pulmonary disease due to either Mycobacterium avium complex (MAC) or Mycobacterium tuberculosis with those in healthy, skin test-negative, control subjects. Significant IFN-gamma responses to ESAT-6 were detected in 16 (59%) of 27 M. tuberculosis pulmonary disease patients, 0 (0%) of 8 MAC disease patients, and 0 (0%) of 8 controls. Significant IFN-gamma responses to M. tuberculosis purified protein derivative were detected in 23 (85%) of 27 M. tuberculosis disease patients, 2 (25%) of 8 MAC disease patients, and 5 (63%) of 8 healthy controls. M. avium sensitin was recognized in 24 (89%) of 27 M. tuberculosis disease patients, 4 (50%) of 8 MAC disease patients, and 1 (13%) of 8 controls. IFN-gamma responses to ESAT-6 are specific for disease due to M. tuberculosis and are not observed in patients with MAC disease or in healthy controls.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Antigens, Bacterial / immunology*
  • Bacterial Proteins
  • Female
  • Humans
  • Immunity, Cellular
  • Interferon-gamma / blood
  • Leukocytes, Mononuclear / chemistry
  • Male
  • Middle Aged
  • Mycobacterium avium Complex*
  • Mycobacterium avium-intracellulare Infection / immunology*
  • Mycobacterium tuberculosis*
  • Skin Tests
  • Tuberculin Test
  • Tuberculosis, Pulmonary / microbiology*

Substances

  • Antigens, Bacterial
  • Bacterial Proteins
  • ESAT-6 protein, Mycobacterium tuberculosis
  • Interferon-gamma