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.
- j( Q( o+ X5 M! F7 K) Y9 YWhenhissix-year-olddaughterpulledoutherbabytooth,SongtaoShioftheNationalInstituteofDentalandCraniofacialResearchinBethesda,Md.,washeditofftoprepareitforthetoothfairy.Holdinghisdaughter'spartialtooth,thestemcellresearchernoticedlivingtissueinsideandwonderedwhetheritmightcontainrelativelyyoungstemcells.Shitookthetoothtohislabandfoundthathewasindeedabletoisolatesuchcellsfromthetoothpulpleftinthecrown./ t6 I: W6 e: Z( H8 d
Extractingmorestemcellsfromthelostbabyteethofseven-andeight-year-olds,ShicalledthenewgroupofcellsSHED(stemcellsfromhumanexfoliateddeciduousteeth).Inthelab,theculturedcellsgrewquickly,formingsphere-likeclustersindicativeofafastrateofproliferationnotobservedinstemcellsisolatedfrombonemarroworadultteeth.Notonlydidtheygrowrapidly,butwhenimplantedundertheskinofimmunocompromisedmice,SHEDinducedboneformation--afeatthatstemcellsextractedfromadultwisdomteethcouldnotaccomplish.SHEDcellsalsotriggeredneuralcellformationinthebrainandfatcellgrowth;stemcellsfromadultteeth,ontheotherhand,arenotasgoodatneuralcellgenerationandcannottriggerfatcellgrowthatall.AreportdescribingthesefindingswaspublishedonlinethisweekbytheProceedingsoftheNationalAcademyofSciences.
( b& `4 e; h6 @% B$ C; w5 n8 vOneofthechallengesofstemcellresearchisthatnobodyquiteknowstheextenttowhichtheycanbeusedtoinducegrowthintissuesotherthanthatfromwhichtheywereextracted.Inthatregard,SHEDcellscouldpotentiallyworkbetterthanothertypesofstemcellsbecauseoftheiryouth(andthusfastproliferation)andtheirdemonstratedabilitytoinducethegrowthofseveraltypesofcells.Whenkids'teethfalloutwecansavethem,Shiremarks.Iftheyneed[thestemcellsfrom]themin20years,therewillbenoimmunorejection.Justwhatthoseneedsmightbe,Shicannotsay.Butconsideringthatotherresearchersarealreadyfreezingstemcellsfromumbilicalcords,hemuses,Whydon'twesavethisone?9 t+ |: t3 O8 x4 F

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来源: Scientific American  h: S# A  L' H; }" ]- R9 @: d
发布者: 亦云