Inflammasome activation in bovine monocytes by extracellular ATP does not require the purinergic receptor P2X7. 
Extracellular adenosine triphosphate (ATP) is a second signal for the assembly of the NLR family, pyrin domain-containing 3 (NLRP3) inflammasome, which form a framework to activate caspase 1, leading to the processing and secretion of the pro-inflammatory cytokine interleukin-1β (IL-1β).  The aim of the present study was to investigate the role of the ATP-gated ion channel subtype P2X7 receptor in the inflammasome activation of bovine monocytes.  ATP-induced inflammasome assembly in bovine monocytes was shown by caspase-1 activation and the release of IL-1β by LPS/ATP-stimulated bovine cells.  The IL-1β release depended on potassium efflux but was independent of reactive oxygen generation of bovine monocytes.  Unlike in the human system, a P2X7 receptor antagonist did not block the ATP-induced release of IL-1β of LPS-primed bovine cells.  P2X7 mediated pore formation was observed in subsets of bovine T lymphocytes (CD4+>CD8+) but not in monocytes.  In addition, ATP and 2-MeSATP but not the high affinity P2X7 agonist BzATP induced calcium influx in bovine monocytes.  The data indicate that ROS generation plays no role in the ATP-induced activation of inflammasome in bovine monocytes and that P2X7-mediated pore formation is not necessary for the release of Interleukin-1β.