Evaluation on Potential Contributions of Protease Activated Receptors Related Mediators in Allergic Inflammation

Table 2

Expression of protease activated receptors (PARs) on structural cells.

Cell type	Expression of PARs				Regulator of PARs
	PAR-1	PAR-2	PAR-3	PAR-4	Upregulation	Downregulation
EpC	+; [50, 101]	+; [50, 60, 101, 102]	+; [50, 101]	+; [50]	NE for PAR-2; LPS for PAR-1, -2, -3, and -4 [50]	na
EnC	+; [50, 62, 64–66, 100]	+; [50, 61, 64]	+; [50, 54, 66, 67]	+; [50, 66]	LPS for PAR-1, -2, -3, and -4 [50]; HCMV for PAR-1, -3, and -4 [66]; MMIF for PAR-1 and -2 [64]; TNF-𝛼, IL-1𝛼, and LPS for PAR-2 [63]	Phorbol ester for PAR-2 [63]; sheer stress for PAR-1 [62]
Fibro	+; [68–71, 164]	+; [53, 68–71, 164]	+; [68, 70, 71]	na	Malignancy for PAR-1 and -2 [164]; bFGF for PAR-2 [71]	PGE2 for PAR-2 [72]
SMC	+; [73, 75]	+; [74]	+; [75]	+; [75]	na	PGI2/PGE2 for PAR-1, -3, and -4 [75]
Kerat	+; [76, 82]	+; [11, 76, 82, 103, 104]	+; [76]	na	na	na

EpC: epithelial cell; EnC: endothelial cell; Fibro: fibroblast; SMC: smooth muscle cell; Kerat: keratinocyte; NE: neutrophil elastase; LPS: lipopolysaccharides; HCMV: human cytomegalovirus; MMIF: macrophage migration inhibitory factor; TNF: tumor necrosis factor; IL: interleukin; bFGF: basic fibroblast growth factor; PG: prostaglandin; na: not available.