PAR-2 regulates dental pulp inflammation associated with caries

Protease-activated receptors (pars) are g-protein-coupled receptors that are activated enzymatically by proteolysis of an n-terminal domain. the cleavage and activation of pars by serine proteases represent a novel mechanism by which such enzymes could influence the host inflammatory response. the aim of this study was to determine whether par-2 expression and activation were increased in dental caries. using immunohistochemistry,we showed par-2 to be localized to pulp cells subjacent to caries lesions,but minimally expressed by healthy pulp tissue. trypsin and the par-2 agonist (par2-ap) activated par-2 in an in vitro functional assay. endogenous molecules present in pulp cell lysates from carious teeth specifically activated par-2,but those from healthy teeth failed to do so. the activation of par-2 in vitro was shown to increase the expression of the pro-inflammatory mediator cyclo-oxygenase-2 (cox-2),providing a mechanism whereby par-2 could modulate pulpal inflammation.