Astrocyte-leucocyte interactions and the mechanisms regulating matrix degradation in CNS tuberculosis.

The CNS (central nervous system) has a unique pattern of immune response to infection. TB (tuberculosis) of the CNS is devastating with widespread tissue destruction. In TB, astrocyte-leucocyte interactions are key in regulating MMP (matrix metalloproteinase) activity and are regulated by complex signalling pathways. A synergistic interaction between interferon gamma and monocyte-derived mediators drives high-level astrocyte MMP-9 secretion; this and other networking effects are inhibited by steroids. Better understanding of regulatory mechanisms may identify potential switch points that could be future therapeutic targets.