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.
9 R  m' ]! `' U- Q1 m. N' \* E4 PWhenhissix-year-olddaughterpulledoutherbabytooth,SongtaoShioftheNationalInstituteofDentalandCraniofacialResearchinBethesda,Md.,washeditofftoprepareitforthetoothfairy.Holdinghisdaughter'spartialtooth,thestemcellresearchernoticedlivingtissueinsideandwonderedwhetheritmightcontainrelativelyyoungstemcells.Shitookthetoothtohislabandfoundthathewasindeedabletoisolatesuchcellsfromthetoothpulpleftinthecrown.4 [( m4 ^5 {7 g$ o1 o+ W* X& j  P
Extractingmorestemcellsfromthelostbabyteethofseven-andeight-year-olds,ShicalledthenewgroupofcellsSHED(stemcellsfromhumanexfoliateddeciduousteeth).Inthelab,theculturedcellsgrewquickly,formingsphere-likeclustersindicativeofafastrateofproliferationnotobservedinstemcellsisolatedfrombonemarroworadultteeth.Notonlydidtheygrowrapidly,butwhenimplantedundertheskinofimmunocompromisedmice,SHEDinducedboneformation--afeatthatstemcellsextractedfromadultwisdomteethcouldnotaccomplish.SHEDcellsalsotriggeredneuralcellformationinthebrainandfatcellgrowth;stemcellsfromadultteeth,ontheotherhand,arenotasgoodatneuralcellgenerationandcannottriggerfatcellgrowthatall.AreportdescribingthesefindingswaspublishedonlinethisweekbytheProceedingsoftheNationalAcademyofSciences.
* X+ e% g+ L$ aOneofthechallengesofstemcellresearchisthatnobodyquiteknowstheextenttowhichtheycanbeusedtoinducegrowthintissuesotherthanthatfromwhichtheywereextracted.Inthatregard,SHEDcellscouldpotentiallyworkbetterthanothertypesofstemcellsbecauseoftheiryouth(andthusfastproliferation)andtheirdemonstratedabilitytoinducethegrowthofseveraltypesofcells.Whenkids'teethfalloutwecansavethem,Shiremarks.Iftheyneed[thestemcellsfrom]themin20years,therewillbenoimmunorejection.Justwhatthoseneedsmightbe,Shicannotsay.Butconsideringthatotherresearchersarealreadyfreezingstemcellsfromumbilicalcords,hemuses,Whydon'twesavethisone?+ z8 b& a. ]- d9 Q2 f7 U
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作者: 2 ~5 S& S3 D  H
来源: Scientific American
3 V4 N, a8 y+ o3 D) Q发布者: 亦云