婴幼儿牙齿可能成为新的干细胞来源

韩雪娜

日期: 2003-04-23 今日/总浏览: 1/460
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Yourseven-year-old'sbabytoothmaybeworthalotmorethanthequarterthetoothfairyleftunderthepillow.Scientistshavediscoveredthatthepulpinsidedeciduousteethisatreasuretroveoffast-growingstemcells.Naturally-shedchopperscouldthusprovideaneasilyaccessiblenewsourceofthesesought-aftercellsforclinicalstudiesofstem-celltransplantationandtissueengineering.- n3 `' \$ B8 V; o1 X4 f' R3 N, ?
Whenhissix-year-olddaughterpulledoutherbabytooth,SongtaoShioftheNationalInstituteofDentalandCraniofacialResearchinBethesda,Md.,washeditofftoprepareitforthetoothfairy.Holdinghisdaughter'spartialtooth,thestemcellresearchernoticedlivingtissueinsideandwonderedwhetheritmightcontainrelativelyyoungstemcells.Shitookthetoothtohislabandfoundthathewasindeedabletoisolatesuchcellsfromthetoothpulpleftinthecrown.) F# w5 e+ D( j9 X7 c3 F$ _
Extractingmorestemcellsfromthelostbabyteethofseven-andeight-year-olds,ShicalledthenewgroupofcellsSHED(stemcellsfromhumanexfoliateddeciduousteeth).Inthelab,theculturedcellsgrewquickly,formingsphere-likeclustersindicativeofafastrateofproliferationnotobservedinstemcellsisolatedfrombonemarroworadultteeth.Notonlydidtheygrowrapidly,butwhenimplantedundertheskinofimmunocompromisedmice,SHEDinducedboneformation--afeatthatstemcellsextractedfromadultwisdomteethcouldnotaccomplish.SHEDcellsalsotriggeredneuralcellformationinthebrainandfatcellgrowth;stemcellsfromadultteeth,ontheotherhand,arenotasgoodatneuralcellgenerationandcannottriggerfatcellgrowthatall.AreportdescribingthesefindingswaspublishedonlinethisweekbytheProceedingsoftheNationalAcademyofSciences.0 D! [, x* S- N9 x7 v* ^! D
Oneofthechallengesofstemcellresearchisthatnobodyquiteknowstheextenttowhichtheycanbeusedtoinducegrowthintissuesotherthanthatfromwhichtheywereextracted.Inthatregard,SHEDcellscouldpotentiallyworkbetterthanothertypesofstemcellsbecauseoftheiryouth(andthusfastproliferation)andtheirdemonstratedabilitytoinducethegrowthofseveraltypesofcells.Whenkids'teethfalloutwecansavethem,Shiremarks.Iftheyneed[thestemcellsfrom]themin20years,therewillbenoimmunorejection.Justwhatthoseneedsmightbe,Shicannotsay.Butconsideringthatotherresearchersarealreadyfreezingstemcellsfromumbilicalcords,hemuses,Whydon'twesavethisone?
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来源: Scientific American+ |# M$ O; G/ H- q) y6 Y0 K* F
发布者: 亦云