Changes in T-lymphocyte subsets in lungs and spleens of mice with slowly progressive primary mycobacterium tuberculosis infection: involvement of unconventional T-cell subsets

Scand J Immunol. 1999 Aug;50(2):137-44. doi: 10.1046/j.1365-3083.1999.00563.x.

Abstract

Our previous study showed that the cell-activation responses and cytokine-secretion patterns were different in lungs and spleens of mice with slowly progressive primary Mycobacterium tuberculosis infection. The aim of the present study was to characterize the T-cell subsets in lungs and spleens of mice with a similar infection. The percentages of T-cell subsets were determined by flow cytometry and the absolute numbers were calculated. Spleens of infected mice showed a threefold expansion of CD4+ cells but no change in CD8+ cells, whereas lungs had a threefold increase of both subsets. A significant expansion of CD4-CD8-alphabeta+ [double negative (DN)alphabeta+] subsets was observed in the lungs of infected mice compared with uninfected mice. This was not the case in the spleens of infected mice. In infected mice the CD4-CD8- (DN) population preferentially expressed alphabeta-T-cell receptors (TCR) in the lungs but gammadelta-TCR in the spleens. The percentages of many T-cell subsets were significantly higher in the lungs than in the spleens of both uninfected and infected mice. However, the percentages of CD4+ and CD4-CD8+TCR- subsets in the lungs were significantly lower than in the spleens of infected mice. We also observed some previously unreported T-cell subsets: double positive-TCR- (DPTCR-), DPalphabeta+ and DPgammadelta+. So far their functions are unknown.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Models, Animal
  • Disease Progression
  • Female
  • Lung / immunology*
  • Mice
  • Mycobacterium tuberculosis / immunology
  • Spleen / immunology*
  • T-Lymphocyte Subsets / classification
  • T-Lymphocyte Subsets / immunology*
  • Tuberculosis / immunology*