Dectin-1 agonist curdlan modulates innate immunity to Aspergillus fumigatus in human corneal epithelial cells

(整期优先)网络出版时间:2015-04-14
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·AIM:ToexploretheimmunomodulatoryeffectsofcurdlanoninnateimmuneresponsesagainstAspergillusfumigatus(A.fumigatus)inculturedhumancornealepithelialcells(HCECs),andwhetherC-typelectinreceptorDectin-1mediatestheimmunomodulatoryeffectsofcurdlan.·METHODS:TheHCECswerestimulatedbycurdlanindifferentconcentrations(50,100,200,400μg/mL)forvarioustime.ThenHCECspretreatedwithorwithoutlaminarin(Dectin-1blocker,0.3mg/mL)andcurdlanwerestimulatedbyA.fumigatushyphae.ThemRNAandproteinproductionoftumornecrosisfactor-α(TNF-α)andinterleukin-6(IL-6)weredeterminedbyreal-timequantitativepolymerasechainreactionandenzyme-linkedimmunosorbentassay,respectively.TheproteinlevelofDectin-1wasmeasuredbyWesternblot.·RESULTS:CurdlanstimulatedmRNAexpressionofTNF-αandIL-6inadoseandtimedependentmannerinHCECs.CurdlanpretreatmentbeforeA.fumigatushyphaestimulationsignificantlyenhancedtheexpressionofTNF-αandIL-6atmRNAandproteinlevelscomparedwithA.fumigatushyphaestimulationgroup(P<0.05).BothcurdlanandA.fumigatushyphaeup-regulatedDectin-1proteinexpressioninHCECs,andDectin-1expressionwaselevatedto1.5-to2-foldbycurdlanpretreatmentfollowedhyphaestimulation.TheDectin-1blockerlaminarinsuppressedthemRNAexpressionandproteinproductionofTNF-αandIL-6inducedbycurdlanandhyphae(P<0.05).·CONCLUSION:ThesefindingsdemonstratedthatcurdlanpretreatmentenhancedtheinflammatoryresponseinducedbyA.fumigatushyphaeinHCECs.Dectin-1isessentialfortheimmunomodulatoryeffectsofcurdlan.Curdlanmayhavehighclinicalapplicationvaluesinfungalkeratitistreatment.