Mycobacterium tuberculosis Specific CD8.sup.+ T Cells Rapidly Decline with Antituberculosis Treatment

Biomarkers associated with response to therapy in tuberculosis could have broad clinical utility. We postulated that the frequency of Mycobacterium tuberculosis (Mtb) specific CD8.sup.+ T cells, by virtue of detecting intracellular infection, could be a surrogate marker of response to therapy and would decrease during effective antituberculosis treatment. We performed a prospective cohort study, enrolling between June 2008 and August 2010, of HIV-uninfected Ugandan adults (n = 50) with acid-fast bacillus smear-positive, culture confirmed pulmonary TB at the onset of antituberculosis treatment and the Mtb specific CD4.sup.+ and CD8.sup.+ T cell responses to ESAT-6 and CFP-10 were measured by IFN-[gamma] ELISPOT at enrollment, week 8 and 24. There was a significant difference in the Mtb specific CD8.sup.+ T response, but not the CD4.sup.+ T cell response, over 24 weeks of antituberculosis treatment (p