LAUSR

Emerging data have demonstrated the critical roles of potassium efflux in the innate immune system. However, the role of potassium efflux in TLR3/4 activation and type I interferon (IFN) responses are not well elucidated. In the present study, we found potassium efflux is essential for TLR3/4 signaling, which mediates the expression of IFN and its inducible gene Cxcl10 and proinflammatory cytokine gene TNF-α. Furthermore, pharmacological inhibition of Kv1.3 channel (PAP-1), but not Kir2.1, KCa3.1 or TWIK2, attenuated TLR3/4 receptor activation in macrophages. Mechanistically, PAP-1 suppressed LPS-induced inflammatory function through marked suppressing the activation of JNK mitogen-activated protein kinase (MAPK) and p65 subunit of nuclear factor-kB (NF-kB). Notably, PAP-1 effectively protected mice against Listeria monocytogenes induced infection. Our findings reveal that potassium efflux mediated by the Kv1.3 channel is essential for TLR3/4 activation and suggest that pharmacological inhibition of Kv1.3 may help to treat type I IFN related autoimmune diseases and bacterial infections.