Toll-like receptors (TLRs) are key molecules of the innate immune systems, which detect
conserved structures found in a broad range of pathogens and trigger innate immune
responses. A subset of TLRs recognizes viral components and induces antiviral responses.
Whereas TLR4 recognizes viral components at the cell surface, TLR3, TLR7, TLR8, and
TLR9 recognize viral nucleic acids on endosomal membrane. After ligand recognition, these
members activate their intrinsic signaling pathways and induce type I interferon. In this …