Changes in T‐Lymphocyte Subsets in Lungs and Spleens of Mice with Slowly Progressive Primary Mycobacterium tuberculosis Infection: Involvement of Unconventional T‐Cell Subsets

• Published in: Scandinavian journal of immunology Vol. 50; no. 2; pp. 137 - 144
• Main Authors: Phyu, S, Sornes, S, Mustafa, T, Tadesse, A, Jonsson, R, Bjune, G
• Format: Journal Article
• Language: English
• Published: Oxford, U.K. and Cambridge, USA Blackwell Science Ltd 01-08-1999
• Subjects: Animals; Disease Models, Animal; Disease Progression; Female; Lung - immunology; Mice; Mycobacterium tuberculosis; Mycobacterium tuberculosis - immunology; Spleen - immunology; T-Lymphocyte Subsets - classification; T-Lymphocyte Subsets - immunology; Tuberculosis - immunology
• ISSN: 0300-9475; 1365-3083
• DOI: 10.1046/j.1365-3083.1999.00563.x

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−αβ+ [double negative (DN)αβ+] 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 αβ‐T‐cell receptors (TCR) in the lungs but γδ‐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−), DPαβ+ and DPγδ+. So far their functions are unknown.