(A) Ex vivo IFN-γ production against five unique M. leprae antigens by PBMC of healthy controls without T-cell responses to M. leprae extracts (Controls, n = 30) (○), MB patients (MB, n = 19) (•), PB patients and MB patients with leprosy reactions (PB/Rx, n = 28) (▾), healthy household contacts and endemic controls with T-cell responses to M. leprae extracts [(H)HC, n = 35] (▴), tuberculosis patients without anti-PGL-I antibody or M. leprae-reactive T cells (TB ML−, n = 11) (□), and tuberculosis patients that show significant T-cell responses to M. leprae extracts and/or are seropositive for anti-PGL-I antibody (TB ML+, n = 5) (▪). Median values are indicated by horizontal lines. P values are calculated by the nonparametric Mann-Whitney U test. (B) Ex vivo IFN-γ production against two M. leprae antigens (ML0007 and ML2649) with homologues in M. tuberculosis (Rv0007 and Rv0264). Symbols are as defined for panel A.