ToobtaintherecombinantsolubleproteinoftheextracellularfragmentofhumanTRAILgeneandtoidentifyitsfunctionpreliminarily,thisgenefragmentwasamplifiedfromperipheralbloodmononu-clearcells(PBMC)byRT-PCRandclonedintovectorpGEM-T-Easyforsequenceanalysis.Theexpres-sionvectorpET-30a/TRAILwasthenconstructedbyDNArecombinationmethodwithaHis-taggeneatthefrontoftheTRAILfragment,andtherecombinantproteinwasexpressedinE.coliBL21(DE3).Meanwhile,theexpressedtargetproteinwaspurifiedwithNi-NTAchromatographycolumnandidentifiedbySDS-PAGEandWesternblotting.TheproliferationinhibitionactivityofTRAIL-HiswasdetectedbyMTTassay.PIstainingandWright-GiemsastainingwereusedtodetectthepresenceoftheTRAIL-in-ducedcellapoptosis.ItwasdemonstratedthatthetargetproteinexpressedinE.coliBL21showedthesamerelativemolecularmassasthattheproteinexpectedandcouldberecognizedbyboththeanti-TRAILpolyclonalantibodyandanti-Hismonoclonalantibody.Inaddition,thisproteincouldalsoinhibitprolif-erationofhumanlymphomacelllineJurkatcellsorinduceapoptosisofthiscellline.ItisapparentthatarecombinantsolubleTRAILproteinwithbiologicalactivityisobtainedandthisprospectivestudycanlaysolidfoundationforfurtherresearchonthebiologicalactivityandapplicationintheanti-tumortherapy.
