TBK1 and COVID-19: Interestingly, in samples of respiratory epithelial cells and plasmacytoid dendritic cells from patients with severe COVID-19, there is a decrease of type-I IFNs associated with self-recessive deficiencies in genes that code for the proteins involved in interferon production (e.g. TLR3, UNC93B, TRIF, TBK1, TBK1, IRF3, IRF7, IFNAR1/2, MYD88, GATA2 and IRAK4) (120–126).