OAS1 and dengue disease: Additionally, individual genes with anti-viral effector functions were analysed in ex vivo sorted ILC2 from HC and individuals with DF and DHF and an upregulation of interferon stimulatory genes (ISGs) such as ISG15, IFITM3, OAS1, RSAD2, STAT1 was observed in ILC2 derived from individuals with DF but not from those with DHF (Fig. 3c).