简介:ToconstructandexpressthefusionproteinStx2B-IntiminC300ofEHEC0157:H7,andtofurtherinvestigateitsimmunoprophyiacticpotential,thegeneofStx2B(stx2b)fromEHEC0157:H7chromosomewasclonedintopMD18-Tvector.Thereafter,theamplifiedgenewasclonedintoprokaryoticexpressionplasmidpET-28a(+)-eaeC300,whichwasconstructedpreviously.TherecombinantpasmidpET-28a(+)-stx2b-eaeC300wastransformedintoE.coliBL21(DE3).Afterinducement,theproteinStx2B-IntiminC300wassuccessfullyexpressedandanalyzedwithsodiumdodecylsulfatepolyacrylamidegelelectrophoresis(SDS-PAGE),WesternblottingandN-terminalaminoacidresidualsequencing.Toevaluateitsimmunoprophyiacticpotential,itwasprimarilypurifiedbyion-exchangechromatographyandinjectedinto30BALB/cmicewithAl(OH)3inthesubscapularregion.Tendaysafterthelastboostervaccination,20micewereattackedwithEHEC0157:H7lysateandtheprotectiveefficacywasobserved.Inthepresentstudy,thegeneofStx2B-IntiminC300wassuccessfullyclonedintopET-28a(+)vector.TheresultsofSDS-PAGEandWesternblottingassayshowedthatthefusionproteinwassuccessfullyexpressedintheinclusionbodyform,accountingfor25%oftotalexpressionproducts,anditsmolecularweightwasabout43kDa.TheresultoftheN-terminalaminoacidresidualsequencingshowedthatitwasidenticaltothatofthemoleculardesigned.Thepuritywasabout75%afterprimarypurification.AnimaltestsrevealedthatthefusionproteinStx2B-IntiminC300haselicitedhightiterofprotectiveantibodyrelatively.TheseresultsdemonstratethatthefusionproteinStx2B-IntiminC300issuccessfullyexpressedinprokaryoticexpressionsystemandshowscertainimmunoprophyiacticpotential.
简介:Wehaveconfirmedefficientanti-tumoractivitiesoftheperipherallymphocytestransducedwithap185HER2-specificchimericT-cellreceptorgenebothinmurineandinhumaninourpreviousstudies.TofurthertestthefeasibilityofchimericT-cellreceptorinabonemarrowtransplantationmodel,wefirst,madetwomurinetumorcelllines:MT901andMCA-205,toexpresshumanp185HER2byretroviralgenetransduction.MurinebonemarrowcellswereretrovirallytransducedtoexpressthechimericT-cellreceptorandgene-modifiedbonemarrowcellsweretransplantedintolethallyirradiatedmouse.Sixmonthsposttransplantation,p185HER2-positivetumorcells:MT-901/HER2orMCA-205/HER2wassubcutaneouslyorintravenouslyinjectedtomakemousemodelssimulatingprimarybreastcancerorpulmonarymetastasis.Theinvivoanti-tumoreffectsweremonitoredbythesizeofthesubcutaneoustumororcountingthetumornodulesinthelungsafterIndiainkstaining.ThesizeofthesubcutaneoustumorwassignificantlyinhibitedandthenumberofpulmonarynodulesweresignificantlydecreasedinmouserecipientstransplantedwithchimericT-cellreceptormodifiedbonemarrowcellscomparedwiththecontrolgroup.Ourresultssuggesttheefficientinvivoanti-tumoractivitiesofchimericT-cellreceptorgenemodifiedbonemarrowcells.
简介:WehavedevelopedandtestedchimericT-cellreceptors(TCR)specificforp185HER2.Intheseexperiments,retroviralvectorsexpressingtheN297orN29ξreceptorswereconstructedinpRET6.AmphotropicviralproducercellswereestablishedintheGALV-basedPG13packagingcellline.Ficollpurifiedhumanperipheralbloodlymphocytes(PBL)werevitallytransducedusinganoptimizedprotocolincorporatingactivationwithimmobilizedanti-CD3/anti-CD28monoclonalantibodies,followedbyviralinfectioninthepresenceoffibronectinfragmentCH296.Transducedcellswereco-culturedwithhumantumorcelllinesthatoverexpress(SK-OV-3)orunderexpress(MCF7)p185HER2toassayforantigenspecificimmuneresponses.BothCD4^+andCD8^+T-cellstransducedwiththeN297orN29ξchTCRdemonstratedHER2-specificantigenresponses,asdeterminedbyreleaseofTh1likecytokines,andcellularcytotoxicityassays.OurresultssupportthefeasibilityofadoptiveimmunothempywithgeneticallymodifiedT-cellsexpressingachTCRspecificforp185HER2.
简介:ExposureofnaivemurineCD4^+TlymphocytestosuperantigensuchasstaphylococcalenterotoxinB(SEB)inducesastrongproliferativeresponse.ProlongedexposureorsubsequentrestimulationoftherespondingTcellpopulationwithSEBleadstotheapoptoticeventsofactivation-inducedcelldeath(AICD).ThesignalingmechanismresponsiblefortheAICDisatargetofintensiveinvestigation.However,theprecisedownstreamsignahngpathwaysofSEB-inducedAICDremainsunclear.Ourresultshereshowthatthesequentialactivationofcaspase-1/ICE-hkeandcaspase-3/CPP32-hkecysteineproteasesprobablyplaysaroleinthesignalingtransductionofSEB-inducedAICD,butcaspase-3/CPP32-hkeproteasesactivationdoesnotdependoncaspase-1-likeproteasesactivation.HerbimycinA,aspecificinhibitorofproteintyresinekinases,inhibitcaspase-3/CPP32-1ikecysteineproteasesactivation.However,itdoesnotpreventDNAfragmentationofCD4^+TcellsapoptosisinducedbySEB.TheseresultsindicatethatproteintyrosinekinasespathwayisprobablyinvolvedinthesignalingtransductionofCD4^+TcellsapoptosisinducedbySEBand“crosstalks”withthepathwayofcaspase-3/CPP32-1ikeproteasesactivation.