Evidence of MMP1 ⁺ CXCL5 ⁺ fibroblast populations in TB-diseased human lungs. (A) Representative flow cytometry plot showing the isolation strategy of the PDPN⁺FAP⁺ fibroblast population from the CD45-EPCAM cell fraction. (B) Cumulative data on frequency of PDPN⁺FAP⁺CD90⁺ fibroblasts as a fraction of live lung cells from five separate lung resections. Three separate sections were taken from each TB-diseased lung, corresponding to the most diseased and least diseased tissues areas and an intermediate lung piece, according to the expert opinion of the operating surgeon. The Friedman test was used to ascertain statistical significance between proportion of PDPN⁺FAP⁺ fibroblast between severity groups. (C) Expression of human TB-myofibroblast signature and SPP1⁺CHI3L1⁺ marker genes in the TST challenge site in vivo model. Active TB TST (n = 48): biopsies from participants with microbiologically confirmed pulmonary TB disease within the first month of treatment who underwent TST; latent TB TST (n = 191): biopsies from participants lacking clinical and radiological evidence of active TB disease but with a positive peripheral blood IFN-γ release assay; saline (n = 34): biopsies from participants that received saline under the skin instead of tuberculin. Each dot corresponds to a sample; horizontal lines represent median values. Two-sided Mann–Whitney U test without correct was used. Statistical annotations: P value <0.001 (***), P value < 0.0001 (****).