MMP9 and tuberculosis: We first assessed differences in single transcriptional biomarkers (direct ex-vivo) (Table 2) and found 7 genes were up-regulated in children with culture-confirmed TB (CD14, FCGR1A, FPR1, MMP9, RAB24, SEC14L1 and TIMP2) compared to TST-negative household siblings (Fig. 2A), and 8 were down-regulated (ABR, BLR1, CASP8, CCR7, CD3E, CD8A, IL7R, and TGFBR2, Fig. 2B).