Increase in gamma interferon-secreting CD8(+), as well as CD4(+), T cells in lungs following aerosol infection with Mycobacterium tuberculosis.
Although it is well established that CD4(+) T cells are required for the protective immune response against tuberculosis (TB), there is some evidence that CD8(+) T cells are also involved in the host response to Mycobacterium tuberculosis. There is, however, a paucity of information on the pulmonary CD8(+) T-cell response during infection. We therefore have compared the changes in both CD8(+) and CD4(+) T cells following aerosol infection with M. tuberculosis. There was an observed delay between the peak of infection and the activated T-cell response in the lung. The kinetics of CD8(+) and CD4(+) T-cell responses in the lung were identical, both peaking at week 8, 4 weeks later than the peak of cellular response in draining lymph nodes. Similar changes in activation/memory phenotypes occurred on the pulmonary CD8(+) and CD4(+) T cells. Following in vitro restimulation, both subsets synthesized gamma interferon, a cytokine essential for controlling M. tuberculosis infection. Since lung CD8(+) T cells are actively expanded during aerosol M. tuberculosis infection, it is important that both CD8(+) and CD4(+) T cells be targeted in the design of future TB vaccines.
Feng
C G
CG
Centenary Institute of Cancer Medicine and Cell Biology, Newtown, New South Wales, Australia 2042.
Bean
A G
AG
Hooi
H
H
Briscoe
H
H
Britton
W J
WJ
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D005260:Female; D005434:Flow Cytometry; D007371:Interferon-gamma / Q000276:immunology*; D008168:Lung / Q000276:immunology* / Q000382:microbiology; D018655:Lymphocyte Count; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis; D014376:Tuberculosis / Q000276:immunology*
D007371:Interferon-gamma