To date, at least ten members of the Toll family have been identified. TLRs recognize molecular patterns associated with microbial pathogens and induce antimicrobial immune response. TLR3 recognizes double-stranded (ds) RNA, induces the activation of NF-kB, throμgh MyD88-dependent and -independent pathways, and the production of type I interferons (IFNs). Similar to several other members of the TLR family, TLR3 has been reported to be expressed at a very low level on the surface of human fibroblast cell lines.