TLR2 and tuberculosis: Consistently, among the TB component examined, only stimulation with the TLR2 ligand peptidoglycan (PGN), but neither of the TLR4 ligand lipopolysaccharide (LPS) nor the Gram-negative bacterium Escherichia coli, TDM, ESAT-6 and ManLAM, induced the expression of miR-27a (Supplementary Fig. 1e).