Activation of the NLRP3 inflammasome by intracellular poly I:C

Several RNA viruses can be detected by the inflammasome, which promotes IL-1 beta and IL-18 secretion, but the underlying mechanisms of detection remain unclear. Cytosolic dsRNA is a replication intermediate of many RNA viruses. We show here that transfection of the dsRNA analogue poly I: C activates the NLRP3 inflammasome via a pathway requiring endosomal acidification. This detection is independent of the other poly I: C sensors: TLR3 and MDA5. These results suggest a mechanism by which cytosolic dsRNA produced during viral infection could activate the NLRP3 inflammasome. (C) 2010 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.