Recognition of MPT83 during M. tuberculosis infection in humans.

Antigen-specific T cell responses were measured in PBMC from M. tuberculosis-infected subjects (TB) (n = 28) and tuberculin skin test-negative subjects (TST−ve) (n = 20). (A) T cell proliferation in response to M. tuberculosis CFP (circles) or rMPT83 (triangles) protein at 10 µg/ml was measured by the net incorporation of ³H-thymidine; and (B) T cell production of IFN-γ following antigen stimulation was measured by ELISA. Horizontal lines represent the median for each group. The statistical significances were determined by the Mann-Whitney U-test (****, p≤0.0001).