An experimental drug that boosts production of the immune system protein interferon worsens tuberculosis (TB) in mice, according to scientists from the National Institutes of Health. The drug acts indirectly by drawing certain immune cells, in which Mycobacterium tuberculosis (M.tb) bacteria thrive, to the lungs. The findings may have potential implications for the care of people infected with TB, the authors note. The research is reported in the May 3 issue of Journal of Clinical Investigation, now available online.