The TWIK2 Potassium Efflux Channel in Macrophages Mediates NLRP3 Inflammasome-Induced Inflammation

Abstract

Potassium (K + ) efflux across the plasma membrane is thought to be an essential mechanism for ATP-induced NLRP3 inflammasome activation, yet the identity of the efflux channel has remained elusive. Here we identified the two-pore domain K + channel (K 2P ) TWIK2 as the K + efflux channel triggering NLRP3 inflammasome activation. Deletion of Kcnk6 (encoding TWIK2) prevented NLRP3 activation in macrophages and suppressed sepsis-induced lung inflammation. Adoptive transfer of Kcnk6 −/− macrophages into mouse airways after macrophage depletion also prevented inflammatory lung injury. The K + efflux channel TWIK2 in macrophages has a fundamental role in activating the NLRP3 inflammasome and consequently mediates inflammation, pointing to TWIK2 as a potential target for anti-inflammatory therapies. Potassium efflux is required for NLRP3 inflammasome activation, but the channel mediating the efflux has remained elusive. Di et al. identify the potassium channel TWIK2 as a mediator of potassium efflux and NLRP3 activation in macrophages. Targeting TWIK2 could form the basis for therapeutic approaches in inflammatory injury.