Pathophysiology and biomarkers of acute respiratory distress syndrome

Table 1 Representative pattern recognition receptors (PRRs) and their ligands

Family	Member	PAMPs	DAMPs
TLR	TLR1	Lipopeptides, lipoarabinomannan	Serum amyloid A protein
	TLR2	Lipopeptides, LTA, lipoarabinomannan, mannan, virus structural protein, zymosan, β-glucan	HMGB1, serum amyloid A protein
	TLR3	dsRNA
	TLR4	LPS, virus structural protein	HMGB1, HSP60, HSP70, S100, HA, fatty acid
	TLR5	Flagellin
	TLR6	Lipopeptides, zymosan, β-glucan	HA
	TLR7	ssRNA
	TLR8	ssRNA
	TLR9	CpG-DNA	Histone, mitochondrial DNA, self-DNA-containing immune complexes
NLR	NOD1	DAP-type PGN
	NOD2	MDP
	NLRC4	Flagellin, bacterial secretion systems
	NLRP3	Pore-forming toxins, MDP	Nucleic acid, ATP, uric acid, HA, silica
RLR	RIG-I	dsRNA	Immunocomplex of snRNPs
Immunoglobulin superfamily	RAGE		AGEs, HMGB-1, S100B, transthyretin, amyloid-β peptide, Mac-1 integrin

PRRs pattern recognition receptors, PAMPs pathogen-associated molecular patterns, DAMPs damage (danger)-associated molecular patterns, TLR toll-like receptor, LTA lipoteichoic acid, HMGB-1 high-mobility group box 1, LPS lipopolysaccharide, HSP heat shock protein, HA hyaluronic acid, NLR nucleotide-binding oligomerization domain (NOD)-like receptor, DAP-type PGN diaminopimelic acid containing peptidoglycan, MDP muramyl dipeptide, NLRC4 NLR family CARD domain containing 4, NLRP3 NLR family pyrin domain containing 3, ATP adenosine triphosphate, RLR retinoic acid-inducible gene-I (RIG-I)-like receptor, RAGEs receptor for advanced glycation end products, AGEs advanced glycation end products.

ISSN: 2052-0492