It was recently shown that exosomes from the plasma of patients with mild or severe COVID-19 have the ability to induce NLRP3, caspase-1, and IL-1β mRNA expression in microvascular epithelial cells (HMEC-1) and hepatic endothelial cells (TMNK-1), resulting in the activation of Casp1 and subsequently IL-1β through the NLRP3 inflammasome in these endothelial cells. The gene discussed is CASP1; the disease is COVID-19.