简介:Immunotherapythatspecificallytargetstumorcellsisthepreferredapproachtoinducetumorregression.Overthepastdecade,significantprogresshasbeenmadeindevisingvariousmethodstodirecttheimmunesystemtorespondtotumorcells.Themajorhurdleforsuccessfulimmunotherapyistoovercomeimmunetoleranceinthetumormicroenvironment.Recentclinicaltrialswithdendriticcell-basedvaccination[1,2]andCTLA4blockingantibodies[3]haveshowngreatpromise,thoughcompletecancerregressionisnotalwaysachieved[4].Currently,alternativestrategiespotentiallyleadingtocancereradicationorregressioninanimalorclinicalmodelsarebeingenthusiasticallypursued.InthisissueofCellResearch,Wangetal.reportanovelwaytoinducetumorimmunitybytheuseofirradiatedautologousTcells[5].
简介:Ourpreviousstudiesshowedapredominanceofhighmolecularweightproteingroupintumornuclearmatrices.Contrarytonormalcells,proteinsofthisgrouparepreferentiallyphosphorylated.Phosphoproteinsofhepatomanuclearmatrixareselectivelysubjectedtorapidproteolysis.Byalkalitreatmentandamonoclonalantibodyagainstphosphotyrosylresiduethepresenceoftwohighmolecularweightbandsofphosphotyrosyl-containingproteinswasdetectedinnuclearmatricesoftumorbutnotofnormallivercells.Highmolecularweightproteingroupoftumornuclearmatricesrevealedalsoarapidturnoverandpreferentialincorporationoflabeledaminoacidsselectivelyinhibitedbychloramphenicol.
简介:Acanthamoebaarefree-livingprotozoaorganismsthatliveabroadinnature.PathogenicAcanthamoebacancauseafatalgranulomatousamoebicencephalitisandkeratitis.SomespeciesofAcanthamoebacaninducesometumorcellsapoptosisinvitro.Prom1996wehaveprovedthatAcanthamoebaLstrain(A.lugdunensis-A.quina),firstlygotbyusfromkeratitispatientsinChina,couldinducetumorcells'apoptosis,includingPC12,B16cellsetal.InthisresearchweprovedthatboththebodyandthelysisofAcanthamoebacouldinducemousemelanomaB16cellsapoptosis.Buttheapoptosismechanismwaspoorlyunderstood.
简介:Thec-erbB-2proto-oncogeneencodesa185kDaproteinp185,whichbelongstoepidermalgrowthfactorreceptorfamily.Amplificationofthisgenehasbeenshowntocorrelatewithpoorclinicalprognosisforcertaincancerpatients.ThemonoclonalantibodyA21whichdirectedagainstp185specificallyinhibitsproliferationoftumorcellsoverexpressingp185,henceallowsittobeacandidatefortargetedtherapy.InordertoovercomeseveraldrawbacksofmurineMAb,wecloneditsVHandVLgenesandconstructedthesingle-chainFv(scFv)throughapeptidelinker.TherecombinantscFvA21wasexpressedinEscherichiacoliandpurifiedbytheaffinitycolumn.SubsequentlyitwascharacterizedbyELISA,Westernblot,cellimmunohistochemistryandFACS.Alltheseassaysshowedthebindingactivitytoextracellulardomain(ECD)ofp185.BasedonthosepropertiesofscFvA21,wefurtherconstructedthescFv-Fcfusionmoleculewithahomodimerformandtherecombinantproductwasexpressedinmammaliancells.Inaseriesofsubsequentanalysisthisfusionproteinshowedidenticalantigenbindingsiteandactivitywiththeparentantibody.Theseanti-p185engineeredantibodieshavepromisedtobefurthermodifiedasatumortargetingdrugs,withaviewofapplicationinthediagnosisandtreatmentofhumanbreastcancer.
简介:ImmunizationwithinactivatedautoreactiveTcellsmayinduceidiotypeanti-idiotypicreactionstodepleteautoreac-tireTcells,whichareinvolvedinautoimmunediseases.However,itisunknownwhetherattenuatedactivatedhealthyautologousT-cellimmunizationcouldincreaseanti-tumorimmuneresponses.Tothisend,C57B1/6micewereimmunizedwithattenuatedactivatedautologousTcells.Thesplenocytesfromimmunizedmiceshowedahigherproliferativeabil-itythanthatfromnaivemice.ThespecialphenotypeanalysisshowedthatthereweremoreCDS+TcellsandCD62L+Tcellsinimmunizedmiceafter24hofculturewith10%fetalcalfserumcompletemediuminvitro(P<0.01).TheseresultsdemonstratedthatthisimmunizationmayactivateTcellsinvivo.Furthermore,thesplenocytesfromimmunizedmicerevealedresistancetoactivation-inducedcelldeath(AICD)invitro.TofurtherstudytherelativegenesthatareresponsibleforthehigherproliferationandresistancetoAICD,theexpressionofFas/Fasligand(FasL)andGADD45βwasmeasuredbyreal-timePCR.TheresultsindicatedthatGADD45βtranscriptionwashigherinthesplenocytesfromimmunizedmicethanthatinthenaivemice.Inaddition,theFasexpressionshowedaparallelhigher,butFasLdidnotchangeobviously.Toinvestigatethebiologicfunctionsinducedbyimmunizationinvivo,atumormodelwasestablishedbyEL-4tumorcellinoculationinC57/B1mice.MicereceivingautologousT-cellimmunizationhadsignificantlyinhibitedtumorgrowthinvivo(P<0.01).ThisstudyimplicatedthatimmunizationwithattenuatedactivatedautologousTcellsenhancesanti-tumorimmuneresponsesthatparticipateintumorgrowthinhibition.
简介:Galα(1,3)Gal(galepitope)isacarbohydrateepitopeandsynthesizedinlargeamountbyα(1,3)galactosyltransferase[α(1,3)GT]enzymeonthecellsoflowermammaliananimalssuchaspigsandmice.Humanhasnogalepitopeduetotheinactivationofα(1,3)GTgenebutproducesalargeamountofantibodies(anti-Gal)whichrecognizeGalα(1,3)Galstructuresspecifically.Inthisstudy,areplicationdeficientrecombinantadenoviralvectorAd5sGTcontainingpigα(1,3)GTcDNAwasconstructedandcharacterized.Adenoviralvector-mediatedtransferofpigα(1,3)GTgeneintohumantumorcellssuchasmalignantmelanomaA375,stomachcancerSGC-7901,andlungcancerSPC-A-1wasreportedforthefirsttime.ResultsshowedthatGalepitopedidnotincreasethesensitivityofhumantumorcellstohumancomplement-mediatedlysis,althoughhumancomplementactivationandthebindingofhumanIgGandIgMnaturalantibodiestohumantumorcellswereenhancedsignificantlyafterAd5sGTtransduction.AppearanceofgalepitopeonthehumantumorcellschangedtheexpressionofcellsurfacecarbohydratesreactingwithUlexeuropaeusI(UEAI)lectins,Viciavillosaagglutinin(VVA),Arachishypogaeaagglutinin(PNA),andGlycinemaxagglutinin(SBA)todifferentdegrees.Inaddition,noeffectofgalepitopeonthegrowthinvitroofhumantumorcellswasobservedinMTTassay.