NLRP3 and COVID-19: Collectively, these findings are consistent with activation of the NLRP3-inflammasome pathway in both lungs and blood and also corroborate previous observations showing elevated Casp1p20 levels in COVID-19 patients and inflammasome activation in patient-derived PBMCs and in CD14+ macrophages resident in COVID-19 lung tissue (17, 29, 35, 36).