Tackling tissue destruction in tuberculosis.

Drug-resistant tuberculosis (TB) is a major worldwide problem. The immune system usually controls TB, but once active disease develops, the inflammatory immune response drives tissue destruction. Tissue damage is a result of enzymatic activity, and matrix metalloproteinases (MMPs) have a key role. There are a few new anti-mycobacterial drugs in trial and some vaccine candidates in development but options for control of TB are limited. A novel approach may be to combine antibiotic therapy with limiting the activity of the key mediators of tissue damage, such as MMPs, by inhibiting either the enzymes directly or the pathways that regulate them.