To dissect the regulatory mechanism of COVID-19 patient–derived EV-induced proinflammatory cytokines/chemokines upregulation, we used the HEK-hTLR7/8 cell model (Invivogen, USA) to examine COVID-19 patient–derived EVs and miR21/let-7b-loaded pEVs modulation on NF-κB activity upon TLR7/8 engagement. The gene discussed is TLR7; the disease is COVID-19.