Toll-like receptors (TLRs) recognize the pathogen-associated molecular patterns (PAMPs) and play a pivotal role in modulating the immune response against invading pathogens. To date, many teleost TLRs have been identified by genome and transcriptome analysis. The orthologs involved in the TLR signalings have also been identified in teleosts. The comparison of the TLR functions in teleosts and mammals may provide significant information that will aid our understanding of host-pathogen interactions in teleosts. In this paper, we summarize of the literature regarding teleost TLRs, focusing on the similarities and differences between TLR mechanisms in teleosts and mammals. In addition, perspectives for future studies on teleost TLRs and the application of TLRs to aquaculture are discussed.
