Use of a T Cell–Based Assay for Monitoring Efficacy of Antituberculosis Therapy

Abstract

Monitoring the efficacy of antituberculosis therapy is crucial both for the individual patient and for better control of the spread of tuberculosis. We studied 18 patients with microbiologically confirmed tuberculosis, both at the time of diagnosis and 3 months after they started therapy, using an in vitro assay that detects T cell-mediated interferon- gamma response to selected peptides of Mycobacterium tuberculosis-specific early secretory antigenic target 6 (ESAT-6) protein. All patients had positive results at diagnosis; however, 3 months later, the response to ESAT-6 peptides was still detectable only in the 5 patients with microbiological isolation and/or absence of clinical improvement after treatment. On the basis of these data, we conclude that our assay is a useful tool in monitoring the efficacy of antituberculosis therapy.

Temporal interferon-gamma release response to Mycobacterium kansasii infection in an anorexia nervosa patient

“…The decreasing kinetics observed for the IGRA response upon treatment of M. kansasii disease were similar to those reported for TB or latent TB, although this pattern was not observed in all studies (Bocchino et al, 2010;Carrara et al, 2004;Chiappini et al, 2012;Katiyar et al, 2008;Kobashi et al, 2009a;Mori, 2009;Pai et al, 2006). Several hypotheses were raised for these discrepancies, such as reinfection in high burden settings, persistence of effector T-cells and within-subject variability (Chiappini et al, 2012;Ewer et al, 2006;Pai et al, 2006;van Zyl-Smit et al, 2009).…”

Two-Year Follow-up Study of Mycobacterium tuberculosis Antigen-Driven IFN-γ Responses and Macrophage sCD14 Levels After Tuberculosis Contact

“…Individuals with a strong IFN-c response to the ESAT-6 compared to those with low IFN-c response had a tenfold increased risk of subsequently developing clinical TB in the 1-2-year period after the exposure [11]. This observation was consistent with the fact that successful antituberculosis therapy was found to decrease the level of IFN-c in response to specific M.tb antigens, ESAT-6 and CFP-10 [31][32][33]. Adetifa et al [34] reported a rising qualitative and quantitative ELISPOT counts of IFN-c producing T lymphocytes in response to ESAT-6/CFP-10 peptides in a close TB contact in Gambia, who developed active disease over a 5-month period.…”

Peripheral Blood CD8 T Cell Response in Different Phases of MTB Infection

“…ATB patients presented a positivity in the typical range of 70-85%, established with IFNγ-based assays [ 11 ]; recent contacts are reported to have about 50% probability of MTB infection (43% established in our RC group), and the positivity of 38% in HW does not differ from the OSHA annual occupational TB risk for 50 bed-wards with more than 100 admissions for TB per year, equivalent to 34.5% [15]. Indeed, the response to the RD1 antigens was shown to be lower in MTB-infected subjects without active disease than in ATB patients, and decreased under effective chemotherapy treatment together with the bacterial load [ 16,17 ].…”