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Chapter7Cellulartherapy
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Mostdiseaseshavecellulariybetraplebiochemicalimbalabecorrectedbydrugs.Thecellsreturntoanear-normalstateafeelsbetter.Someplexdiseasesstartwithgepreventaparticularproteinbeingexpressedetheproteinstrusuchawaythatitsfunisalteredoriive.Evenwiththedbalaernalrepairorcellsuiegenegesesd,whehefualcellprocesses,theyhaveadevastatiohorfuncreasedgrowthcausedbygeotheslipperyslopeofcerwherethese‘outoftrol’cellsfurthergetheirgeiddeveloptheabilityforlimitlessdivisionand,insomecases,gaiytoiissues.Ireatingsuchdiseasesrequiresthattheerrantcellsareremoved,corrected,oreveerreplayotherdiseasesarelylifethreateningbutotbecorrectedbydrugtreatmeheirplexbioature.Theidealsolutiothediseaseatitsrthefaultycells.Thisprocessiscalledcellulartherapyandbedividediforms.Themostfamiliaristhetransplantationofmaturefunalcells,asinabloodtransfusion,andstemcellsasiransplaillawaitastandardtherapyfortheintroduodifiedhumanorareplacearequiredsubstance,susulin-produgcellsfordiabetics.
MaheSwissphysidalchemistPhilippusAureolusParacelsusasthefirstpersoheceptofcelltherapyinhisbrossenWuSurgeryBook’)publishedin1536ie:‘thehearthealstheheart,luheluhespleen;likecureslike’.Thisremarkhistheorythateatihyanimalanswouldrebuildaalizetheparticularageingorfaultyaritionistdoethanoneofamoderherapist.Aslongagoas1667,Jean-BaptisteDenis,wintheroyallaboratoryofLouisXIV,attemptedtotransfusebloodfromaentallyillpatiere-bloodtransfusiono1912hysistriedtotreatsufferingfromuivethyroidlahyroid1931,aSwissPaulhe‘fatherofcelltherapy’byatwheroduethyroidtissueintoarapidlydeteripatienteriencedseveredamagetlandsdurihepatientredlivedforafurther30years.Niehansbeownedforhiscellulartreatments,andhispatientsincludedmembersofvariousRoyalfamilies,PopePiusXII,politidfamousfilmstars.Hisnameaments,especiallyskiyprocesses,liveonatthePaulNiehansidedinSwitzerlandbyhisdaughter.The20thturyislitteredwithstoriesofso-calledcellulartherapies.JohnBrinkley,knowglanddoctor’,reportedlydid16,000operationsiedmenwithtissuefromthetesticlesofyounggoats,assertingthatthisprocedurewaseffectiveagainstimpotendcouldditifromasanity.Hislicewasrevokedonthegroundsofimmoralityandunprofessionalduct.JamesWilsoheuseofboviissuecells.Heclaimedthatsuchcellularpreparatioh‘havetheabilitytomigratetoanytissueinneedofrepairahesite,takeoeristicsofthehealthycellitassociateswith’.Otherattemptsalongsimilarlinesdredsofdeathsbyvioleionstobacterialorviraliionsingtwomenwhodiedofgasgangrenefollowiioalsheepcells.Other,eveionableembryoransplanttherapieswerepioneeredbyNiehansinSwitzerland.Inthe1970s,hisstudentWolframKuhupaMexico,wheretherewereions,usingembryonicbluesharkcellspurchasedofflocalfishermenandwithadubiousnumberoflivecells,to‘treat’patientsforawiderangeofdiseases.Asaresultofthis‘quadthebadpressitreceived,itisherewasahighdegreeofscepticismaboutcell-basedtherapiesasroachedthe21sttury.
Transplantationofbloodcells
Bloodtransfusionusinganimalbloodstartedihturybutwasunsuccessfulbecauseofbloodgroupinpatibilityaions.SuchwasthedeathtollthattransfusionwasbahroughoutEuropeforover150years.Arouurhtury,KarlLandsteinerdisanbloodgroups(A,B,AB,O),forwhichhereceivedtheNobelPrizein1930.Mixingbloodfromindividualswithinpatiblegroupsleadstobloodglutination.Landsteinerdiscoveredthatthisprocesswasduetoanimmunologicalreabetweendissimilarbloodgroups.Theclassifiofbloodgroupsisbasedonthepresenceorabsenheritedantigens,ingproteins,carbohydrates,andlipids,onthesurfaceoftheredbloodcells.Ifinpatiblebloodisiibodiesi’sbloodplasmaattaewredbloodddestroythemiioncalledhaeminrenalfailureandcirculatoryshock.Bloodtransfusionisnowaroutineprodmostblooddonatioioheirpoheseincluderedbloodcells,platelets,whitebloodcells,plasma,andvariousproteinssutibodiesandgfactors(seeChapter5).Seleposallowforspeeios,auseofaunitofblood.Forexample,plateletshelprestoretheblood’sgabilitywheopeoplewithtoofewplatelets(thromboia),aleadingtosevereandspontaneousbleedingandwhiesasideeffeotherapy.Whilethetransfusionofwhitecellsisrarefiions,ithasbeeherapywhenthecellshavebeeiipulatedtoeliti-tumourcellactivity.
Inthe1970s,EdwardDonnallThomasdemobonemarrowfusedintravenouslyrepopulatethebonemarrorodualbloodcells,workforwhichhereceivedtheNobelPrizein1990.Theactivetheserepopulatiiobloodstemcells.Cytsrequiredforcertreatmeroyalldividingdtlydonotdisatebetweentumourdbloodstemcells.Replagthepatient’sstemcellsfollowiherapyreplehebonemarrowcellpopulationaheresumptionofnormalbloodcellproduarrolantationhasbeenusedinawiderangeofcertherapiesingleukaemiaandlymphomatorepairbecausedbychemotherapy.Boransplantshavealsobeensuctreatingiaandotherdiseaseswherestemcellsaredamagedorabsent.
Autologousbloodstemcelltherapyusesthepatient’sownstemcells,whichareremovedaotreatmeagesofautologoustransplaheyarerelativelyfreeofiionandthereuionismorerapidaologoustransplaalossibleandsoothersourcellsareneeded.Allogeneisplantsihydoissuesmustbeaclosetissuematchtothoseofthepatiehedoive)isgeothepatiehematchofspecificcell-surfas,calledthehistopatibilityplex.EvenasingleDNAbasepairdiffereinginagedaminoaeofthefivehistopatibilityproteiinamismatgboraresareabletosequeheDNAofallfivehistopatibilitygeopatibility.Owilymatchedstemcellsbutueddonorsneedasmanymatismatcreasestheriskofgraftrejeraftversushostdisease.Graftrejeothebodyrejeelantedcellswhilegraftversushostdiseaseothenewcellsrejectthebody.Botheffectsresultinanimmunologicalreathatbefatal.
&reatments,bonemarrowwastakenfreboypicallythepelvis,throughareachesthetreoftheboeiqueisreferredtoasabonemarrowharvestandisperformedundergehesiawithalltherequirementsofhospitalizingthedonor.Nowadaysstembesourgblood.Thismethodedfromahatgstemcreaseddramaticallyfollowiionsofablrowthfarowthfadtheirstemcellsarecollectedbyameicalseparator,afterwhichtheredcellsarereturhedonor.
Itisalsopossibletoisolateusefulamountsofbloodstemniotidtheumbilicalcord.Cordbloodhasahightrationofstemcells,butonlyenoughforbloodstemsplantsinyoung.Usingbinationsofgrowthfactors,itispossibletoamplifytheemtheumbilicalcordallowingpossibleuseinadulttransplants.Umbilicalstemerallyproducelowlevelsofgraftversushostdisease.Steofone’sownumbilicellsforpossiblefutureuseinadultlifehasdevelopedintoanexpandiissuestepanies.
aherapy
Intheearly1960s,mouseembryoniaeshavingstemcellcharacteristicswerederivedfromateratoa.Thiscertissueismadeupofgermcellsthatarederivedfromtheovarydiredirectlyduetobirthdefectsresultingfrembryodevelopmehesecellswashinderedbyproblemsofgeioability.TheisolationofESesfromnormalembryos(seeChapter6)overcamethesedefedbegananewareaofresearch,explthepossibilitiesofisolatingandmanipulatinghumanembryoniccellsforpossibleuseasstemcelltreatmentsinadults.
MouseEScellshavebeeehegeiehesegeiiceareextremelyuseful,astheyactasamodeltostudythefunsofindividualgenesiohumans.Transgenicmicearecreatedbytransferringagene(forexampleahumaedgeoculturedEScells.Alternatively,individualgenesockedout’byintrodugafeenadrugresistaeuhesegenemanipulatiooriouslyi,ahetreatedeedtobegrownindselectedfeheselectedcellsarethenmijetotheinnercellmassofanormalembryobeforeimplantatioerusofafostermothermouse.Thehaveacopyoftheintroduepreseheirpairedes(i.e.theyareheterozygous)aherbredtogainhomozygousstrainsinwhiewgene(orkgene)hasaates,sotheeffectarentiheahegeneisexpressedinaparticulartissueorcelltypewilldependonitsgenomiehatusuallybedirectedattheEScelllevelbycarefulmolecularsele.Therearenowthousandseraihaspeealterationandtheyhavegreatlyenhanderstandingofmanyplexbiologicalprocesses.Wheheoverexpressionehemajorcauseofadisease,transgeniimalsactasamodelfordevelopingnewdrugsorpharmaceutiterventiohesegeiipulationsintrodugesthatresultiuses,esbe‘resdgrownincultureforusefulresearch.
ThereareanumberofpossiblesouranEScells:(i)cadaverfoetaltissue,(ii)embryafterireatments,(iii)embryosmadesolelyforresearchpurposesusingIVF,and(iv)embryosmadeusiraoeggs(theteiqueusedtocreateDollythesheep).AllhumanEScellsourcesraiseethidreligiousquestions.trybytry,pulationusuallyrefiectsthepredomihidreligiousviews,withmanytriespletelyprohibitingallworkonembrystrictregulations,whilesomehavefew,ifaiosofhumaemcellresearchbelievethatahumanlifebeginsassoonasaneggisfertilized.Thedestrubryoisdeemedmorallyasmurder.TheyalsuethatESologiesareafirststeptoreproduing,whidamentallyviolatesahesanctityoflife.Propuethatiuralreproduaeilizedbutfailtoimplaerus.Afertilizedegg,whileitmaybeinghumabesideredahumailithasbeensuccessfullyimplantedinawomahemethodsrequiredforIVFroutiemorehumahanarehecourseofafertilitytreatment,leavingexcessembryosthatareoftensimplydisditismorallypermissibletousesuchembryosforpotentiallylife-savingbiomedicalresearch.ESesfromearly1990sexperimentshavebeeeduseinicaltreatments.
Oneexampleofusireathumaniheapprovalin2009forthefirstphaseoficaltrialsfortransplantationofhumahebrainandspinalcodeorcells),derivedinculturefromhumaopatientswithinjuredspinalcords.ThefirstpatieedinOctober2010byHaeamattheUyofia,IrvineandspohebiotepanyGerosinratshadpreviouslyshownthattherehadbeehereentinanimalswithspinaljuriesafteraseveransplantationofhumahadbeeooligodendroeageihisnewongoingstudytotreatparaplegicswilllastforatleastfiveyears.Whileitisthistreatmentwillpletelycuretheinjury,itishopedthatitwillshowsuffitrepairoftheobeworthwhile.ThisisapistudypromisingabrightfuturefortheuseofEScellsfspinalinjuries.
&hical,religious,andpolitistraintsofisolatingembryoniantherapyhasdriventheresearchdream,ayofindugorde-differentiatingadultbryo-likepluripotecouldbeusediherapy.In2006,ShinyaYamanakaproduducedpluripotentousefibroblastcellsbyftheexpressioneroviruses(aDNAvirusfamilythatissequehehostDoiheexpressioifiedasimportantformaintaiheadultfibroblastcells.Earlyattemptsdidallysuccessfulastheexpressionofsenesceraftertransplantationintothemouseembryo.Thisproblemwasoverein2008byusienes.Uroviruses,thisvirusdoesnotisowhehoste.SeveralgroupsmirroredthesemouseexperimentsinadulthumahefollDingandcolleaguesfounditossibletoatitopluripotehoutoionbutusimentwithtwosmallchemithesizedproteins.Themanipulationofanindividual’sadultcellstoproduic-likecellscapabletheiransandtissuesisprediajoricaltreatmeure.
&ialofusiorepairdiseasedanddamagedanswithouttheriskaionorothersideeffeendpointthatisdrivingmuchresearch.Stemcelltherapiesexistbut,sofar,oalmedicaltreatments.Themainareasressareiingofdmuscledamage,diabetes,liver,Parkinson’sdisease,andHuntingdon’sdisease.
Cardiovasculardisease—inghypertension,aryheartdisease,stroke,aiveheartfailure—isthemajorcauseofdeathinmanytriesaroundtheworld.Whendeprivedofoxygen,cardiacmusclecells(yocytes)dieandthistriggerstheformationofscartissue,theoverloadofbloodfloressure,agofviablecardiaccellsleadifailureah.Usi,andpigmodels,varioustypesofstemgembryonidothelial,andnaturallyheartstemcellshavebeensheedamagedhearttissues.Afewstudiesinhumans,usuallyundergery,haveshownthatstemtroduceddirectlytotheheartortrahebloodcirhavegivenimproveddiionofne>
Musculardystrophyisagroupofgeicdisordersicausesthemusclestoweakenwithtimeauallyleadstoprematuredeath.Theiscausedbytheproteindystrophinwhiaiyofmusgmouseanddogmodels,stemcellscalledmesoangioblasts(programmedtodiffereomusclecells)withacorrecteddystrophingeransplanted.Normaldystrophinlevelsahwereregainedinfouroutofsixdogs,suggestiherapymaybethewayaheadfortreatmentofthisgeicdisease.
In2008,EScellsweretodevelopingintoimmaturebetacellscapableinsulin,whichwereabletoreversediabetesihesameyear,adulthumanskincells,firstiopluripotentcells,rogrammedtoprodu.Amoreexgaspectwasthatthesecellssesulioglucose(astheydonormallyihinthepaisonlyamatteroftimebeforetransplantationofinsulin-produgcellswillreplaeedforalifetimespeinginsulininpeoplesufferingfromtype1diabetes.Similarprogresshasbeeuringliveristemmigliverregeionadistinctpossibility.
ThegraduallossofdnerveareasofthebraisinParkinson’sdisease.Earlycellulartreatmeraalbraintissue.Afewindividualsshorovementandprovidedageneralproofofprifromthetioustissuesource,theseicaltrialsdidhighlightseveralissuesingtheneedfequantitiesofpuredthatthefoetaltransplaedthemselvesbytransmissionofParkinson’sdisease.In2008,induitorstemcellswerecreatedfromskinfibroblastsofmidthenfurtherdiffereoneuronalprecursorcellswhich(follolantatioedintbrain.Thisapproachhasbeeendedinananimalmodelwhichmimison’sdiseasebykillingoffthenormaldcellswithatoxin.Transplantationofiemcellsgaveamarkedimprovemeoedanimals.ThemajeisnowtouandhowParkinson’sdiseasedevelopsaemcellmodelstodeveltreatments.
Huntington’sdiseaseisaivediseasethatischaracterizedbythedeathofhebrainthatproduitterchemical(gammaaminobutyricaicaltreatmentusingstemcellsfton’shasmirroredthatofParkinsoaltissueastemcellsgraftedibrainincreasebrainactivity,ingmions.Stemcellsmayhe‘magicbullet’forthisdiseasebutajorpartofitseffeagement.
Mesenchymalstemcells,foundinthebonemarrow,ducartilage,boendonas,mus,fat,aheyareeasytoisolatefromsmallquantitiesofbonemarrowandarereadilygrowsransplantatioocksareviableandcouldbeusedfor‘offtheshelf’therapies.Theyarealsofoualpulp,thesofttissueih.Wisdomteethareaparticularlyrichsourdthisopeingpossibilityofvisitiforastemsplant.Embryonichymalstemcellshavebeentrahejawbomieofthese‘trewintofullyfunalhardteethcapabletopaiooth-derivedstembepersuadedtehremaianIndianbiotepaheworld’sfirstdentalstemk.
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