Table 5

Examples of PRRs, their ligands (PAMPs) and their origin

 TLR1Triacylated lipopeptidesBacteria
 TLR2PeptidoglycanBacteria, viruses
 TLR3Double-stranded RNAVirus
 TLR6Diacylated lipopeptidesBacteria, viruses
 TLR7 (human TLR8)Single-stranded RNAVirus, bacteria
 TLR9CpG-DNAVirus, bacteria
 NOD1γ-d-Glutamyl-mesodiaminopimelic acidBacteria
 NOD2Muramyl dipeptideBacteria
RIG-I-like receptors
 DDX58 (alias: RIG-I)Short double-stranded RNAViruses
 IFIH1 (MDA5)Long double-stranded RNAViruses
Cytosolic DNA receptors
 MB21D1 (alias cGAS)
Double-stranded DNAVirus, bacteria
C-type lectin receptors
  • AIM2, absent in melanoma 2; cGAS, cyclic GMP-AMP synthase; CpG-DNA, DNA containing the unmethylated phosphate-guanine (CpG) dideoxynucleotide motif; IFI16, interferon, gamma-inducible protein 16; MINCLE, macrophage inducible C-type lectin; NLR, NOD-like receptor; NOD, nucleotide-binding oligomerisation domain; PAMP, pathogen-associated molecular patterns; PRR, pattern recognition receptor; RIG-I, retinoic acid-inducible gene I; ZBP1, Z-DNA binding protein 1, MB21D1, Mab-21 domain containing 1; TLR, toll-like receptor.