RIGI and COVID-19: The induction of cytokine production in MNPs in COVID-19 can either be triggered via recognition of damage-associated molecular patterns (DAMPS) released from epithelial cells affected by SARS-CoV-2 by PRRs or by direct recognition of viral pathogen-associated molecular patterns (PAMPs) via specific Toll-like receptors, i.e. TLR2 and TLR4, the retinoic acid-inducible gene I (RIG-I) or the melanoma differentiation associated gene (MDA)-5 (116–119).