(A) Genetic background of the test population. Normalized responses of 5864 peptides detected in all 34 patients with TB+ from Armenia patients and 4733 peptides detected in all 6 TB+ patients from Sweden. Peptides recognized by one patient group but not the other are assigned the minimum detectable response (approximately −1.0). Peptides that were not recognized in any of the 35 healthy controls are highlighted in red. (B) Differential epitope recognition in IgA and IgG responses in patients with TB. Material from 6 individuals with TB, recruited in Stockholm, was tested for IgA and IgG responses directed against the MTB peptide library. Three groups of peptides are apparent (supplementary Table S6a–c online): those recognized by both IgG and IgA (n = 2544 peptide species, supplementary Table S6a) only by IgG (n = 1703 peptides, supplementary Table S6b), or only by IgA (n = 845 peptides, supplementary Table S6c). For peptides not recognized by IgG, we assigned the minimum detectable response (approximately −1.0) on the plot, and similarly for IgA. Peptides recognized by both IgG and IgA are strongly correlated (r = 0.75).