Mycobacterium tuberculosis-specific cellular immune profiles suggest bacillary persistence decades after spontaneous cure in untreated tuberculosis.
Individuals with self-healed tuberculosis from the preantibiotic era offer a unique insight into the natural history of and protective immunity to tuberculosis. In 27 such persons whose tuberculosis self-healed >50 years earlier, circulating Mycobacterium tuberculosis antigen-specific interferon γ (IFN-γ)- and interleukin 2 (IL-2)-secreting T cells were detected ex vivo in 16 and 19 individuals, respectively. The M. tuberculosis-specific T cell cytokine profile was dominated by effector memory T cells that secrete both IFN-γ and IL-2 and included T cells that secrete only IFN-γ or IL-2, suggesting persistence of antigen secreted by viable bacilli. Of 10 individuals with no M. tuberculosis antigen-specific IFN-γ-secreting T cells detectable ex vivo, 7 had evidence of central memory T cells, consistent with clearance of infection.
Tuberculosis Research Unit, Department of Respiratory Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
Kerry A
KA
Millington
Sarah
S
Gooding
Timothy S C
TS
Hinks
D John M
DJ
Reynolds
Ajit
A
Lalvani
D000368:Aged; D000369:Aged, 80 and over; D004739:England; D058501:Enzyme-Linked Immunospot Assay; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000032:analysis*; D007376:Interleukin-2 / Q000032:analysis*; D008297:Male; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D011859:Radiography; D011795:Surveys and Questionnaires; D013601:T-Lymphocytes / Q000276:immunology*; D014376:Tuberculosis / Q000000981:diagnostic imaging / Q000276:immunology*
D007376:Interleukin-2; D007371:Interferon-gamma