AIM:ToidentifythefunctionofST2andexploretheroleofIL-33/ST2signalinginregulatingthepro-allergiccytokineproductioninhumancornealepithelialcells(HCECs).METHODS:HumancornealtissuesandculturedprimaryHCECsweretreatedwithIL-33indifferentconcentrationswithoutorwithdifferentinhibitorstoevaluatetheexpression,locationandsignalingpathwaysofST2inregulatingproductionofpro-allergiccytokineandchemokine.TheexpressionofmRNAwasdeterminedbyreversetranscriptionandrealtimePCR,andproteinproductionwasmeasuredbyenzyme-linkedimmunosorbentassay(ELISA),immunohistochemicalandimmunofluorescentstaining.ST2proteinwasdetectedindonorcornealepithelium,andST2signalwasenhancedbyexposuretoIL-33.·RESULTS:IL-33significantlystimulatedproductionofpro-allergiccytokinesthymicstromallymphopoietin(TSLP)andchemokine(CCL2,CCL20,CCL22)inHCECsatbothmRNAandproteinlevels.Thesestimulatedproductionsofpro-allergicmediatorsbyIL-33wereblockedbyST2antibodyorsolubleST2protein(P<0.05).Interestingly,theIκB-αinhibitorBAY11-7082orNF-κBactivationinhibitorquinazolineblockedNF-κBp65proteinnucleartranslocation,andalsosuppressedtheproductionsofthesepro-allergiccytokinesandchemokineinducedbyIL-33.CONCLUSION:ThesefindingsdemonstratethatIL-33/ST2signalingplaysanimportantroleinregulatingIL-33inducedpro-allergicresponses.IL-33andST2couldbecomenovelmoleculartargetsfortheinterventionofallergicdiseasesinocularsurface.
