Finally, circulating γδ T cells decreased significantly in IFN-γ production and increased IL-17 compared to HDs [39], while gene expression of circulating γδ T cells between healthy donors and individuals with COVID-19 showed the IL1B was expressed as well as IL1A and TNF [44], though the levels of IL-1β, IL-6, IL-1RA, IFN-γ and IL-17 in supernatants of endotracheal aspirates (ETAs) were higher than serum [39]. Here, IFNG is linked to COVID-19.