Breathing in asbestos and silica has long been known to cause lung damage, but how the damage occurs has been a mystery. Using mice, scientists have now zeroed in on a key player known as the Nalp3 inflammasome, a complex of proteins that serves as a potent alarm system in our bodies. Evidently, when the body breaks down inhaled asbestos fibers, it ultimately produces reactive oxygen that triggers the inflammasome, which in turn causes lung inflammation. Mice that lack the Nalp3 inflammasome have a reduced reaction to asbestos. According to study co-author Jürg Tschopp of the University of Lausanne in Switzerland, the finding suggests that people exposed to asbestos should be checked for inflammation of the lung, which may be apparent 10 years after exposure. Also, because Nalp3 lies behind other immune reaction conditions, such as gout, the team speculates that gout medicine might slow the progression of inflammatory lung disease. Science published the results online April 10.