Quantitative T-cell interferon-gamma responses to Mycobacterium tuberculosis-specific antigens in active and latent tuberculosis

Eur J Clin Microbiol Infect Dis. 2009 Jun;28(6):667-70. doi: 10.1007/s10096-008-0670-8. Epub 2008 Nov 20.

Abstract

The objective was to compare the quantitative T-cell responses measured by the commercial interferon-gamma (IFNgamma) release assays (IGRAs) in active and latent tuberculosis (TB) states. T-cell responses of culture-proven TB cases were compared with those of contacts with positive IGRA results and tuberculin skin tests >or= 15 mm. T-SPOT.TB results in 270 active TB cases and 183 community contacts showed the median spot-forming cells (SFCs) above negative control/2.5 x 10(5) peripheral blood mononuclear cells to be 27 (-1 to 203) vs 10 (-2 to 174) in response to ESAT-6 (p < 0.001); and 37 (0 to 293) vs 13 (0 to 225) to CFP-10 (p < 0.001). The median IFNgamma levels (antigen minus nil control) as measured by QuantiFERON-TB Gold In-tube in 270 cases and 142 contacts in congregate settings was 2.3 IU/ml (-0.58 to 31.44) vs 1.7 IU/ml (0.35 to 26.51, p = 0.98). Quantitative T-cell responses as measured by the T-SPOT.TB may indicate mycobacterial burden and disease activity, but cannot be used to discriminate active from latent TB.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Bacterial / immunology*
  • Humans
  • Immunoenzyme Techniques / methods
  • Interferon-gamma / metabolism*
  • Mycobacterium tuberculosis / immunology*
  • T-Lymphocytes / immunology*
  • Tuberculosis / diagnosis*
  • Tuberculosis / immunology*

Substances

  • Antigens, Bacterial
  • Interferon-gamma