运动医学未翻

USEOFBIOREACTORSINAUTOLOGOUSCHONDROCYTECULTUREOVERTHREEDIMENSIONALBIODEGRADABLESCAFFOLDSTOREPAIRARTIFICIALLYCREATEDCHONDRALDEFECTSINRABBIT.By:Dr.KumarPriteshDeptt.OfOrthopaedicsGuide:-Prof.A.RastogiDepttofOrthopaedicsIMSBHUCo–Guides:Dr.PradeepSrivastavaSchoolofBiochemicalEngineering,IITBHUDrAmritaGhoshkarDeptt.oFPathologyIMSBHUAHOPELESSSITUATIONINDEED

??RECONSTRUCT?AIMSANDOBJECTIVES:

WHYACCPRODUCTIONON3DSCAFFOLDS??Articularcartilagedefect–amajorhealthproblemduetolimitedcapacityofself-regeneration.Leadstopainandosteoarthritis.Traumacausinginjurytosubchondralbone–fibrocartilagetissue–badcartilage.Partialthicknessinjury–avascularhealing–poorTissuecultureofcartilageiscostly.Culturedchondrocyteshavetendencytode-differentiate.Transplantedcellscanleakintojoint,sizeofdefectislimited,requiresintactadjacentcartilage.HYPOTHESIS:Thesolution3-Dbiodegradablescaffoldsprovidethenecessarymatrixstructureforchondrocytes.bio-reactorproducesbetteryieldandqualityofcartilagecellsbysimulatingstressandstrainconditionsofjoint.impregnatedchondrocyteshavenochanceofleakagedonotrequireopentechniqueasnosuturesinvolved.bio-degradablescaffoldsdonotactasforeignmaterialmaterialischeap–samewhichweuseinabsorbablesutures.futureadvancementwithtopographicalimagingcanhelpusbuildcustomised3Dreplicaofthe“missing”pieceandtheyarethematerialofchoicefortheimplant.

METHODOLOGYDefectsof2.5mmdiameternotextendingtothezoneofcalcificationwillbecreatedinarticularcartilageofbothkneeofeachrabbitinthenonweightbearinginter-condylarregion.

METHODOLOGYBitsofcartilagethusobtainedwillbeculturedafterisolationandinitialprocessingoverthreedimensionalbiodegradablescaffoldsundercontrolledbiophysicalconditionsinabioreactorfor2wksMETHODOLOGYBitsofcartilagethusobtainedwillbeculturedafterisolationandinitialprocessingoverthreedimensionalbiodegradablescaffoldsundercontrolledbiophysicalconditionsinabioreactor

for2wksMETHODOLOGYx2wksAirliftBio-ReactorBitsofcartilagethusobtainedwereculturedafterisolationandinitialprocessingoverthreedimensionalbiodegradablescaffoldsundercontrolledbiophysicalconditionsinabioreactor

for2wksMETHODOLOGYReplantationTheseculturedchondrocytesoverthescaffoldwerere-implantedintoonekneeandtheotherkneeactsasthecontrol

METHODOLOGYReplantationTheseculturedchondrocytesoverthescaffoldwillbere-implantedintoonekneeandtheotherkneeactsasthecontrol

MethodologyReplantationTheseculturedchondrocytesoverthescaffoldwillbere-implantedintoonekneeandtheotherkneeactsasthecontrol

TOTALRABBITSOPERATEDA4weeksX(diedpostop)BC8weeksBoththekneejointsofrabbitshallbeassessedperiodicallyat4,8,12histologicallyaftersacrificingthelimb.TOTALRABBITSOPERATEDD4weeks12weeksEF4weeksBoththekneejointsofrabbitshallbeassessedperiodicallyat4,8,12histologicallyaftersacrificingthelimb.TOTALRABBITSOPERATEDGHI8weeks8weeks12weeksBoththekneejointsofrabbitshallbeassessedperiodicallyat4,8,12histologicallyaftersacrificingthelimb.J12weeksK12weeksL8weeksTOTALRABBITSOPERATEDBoththekneejointsofrabbitshallbeassessedperiodicallyat4,8,12histologicallyaftersacrificingthelimb.ElectronMicroscopyofscaffoldstructureAssessmentPreparationAssessmentPreservationandfixinginformalin4WEEKS8WEEKSControlImplantControlImplant12WEEKSMicroscopyandhistopathologyProliferationofchondrocytesnearinjurysiteR

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FAssessmentMicroscopyandhistopathologyDenseinflammationwithcartilagedefectAfter4weeksControlImplantProliferativegrowthatthejunctionwithinflammationandgranulationtissue,bednottakenupyetjunctionR

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FImplantsitehealingwithinflammationandsimultaneousproliferationNormalepitheliumInjuredepitheliumhealingnormallybyfibrosisHighpowerviewshowingproliferatingNestsofchondrocytes

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HAssessmentMicroscopyandhistopathologyControlImplantAfter8weeksNormalhealingbyfibrosisandproliferationCartilagelobuleshavingimmaturecartilage,bonytrabeculaeandhealingbybothfibrosisandproliferationR

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cAssessmentMicroscopyandhistopathologyAtJunctionControlImplantAfter8weeksNormalmaturationattheinjurysitewithcartilaginouscapat10o’clockpositionInjurysiteshowingdegradedscaffoldmaterial,cartilaginouscapisthinandbonytrabeculaeareabsentR

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EAssessmentMicroscopyandhistopathologyAtJunctionControlImplantAfter12weeksThedefectandnormalcartlaginousepitheliumRegulargrowthattheimplantsitewithcoalitionatthejunctionR

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EAssessmentMicroscopyandhistopathologyAtJunctionControlImplantAfter12weeksBonylamellaeandpletehealingnotcoveredbycartilagejunctionnormalProliferativegrowthatgraftsiteandUptakeatthedefectbedwithcoalitionwiththejunctionDISCUSSIONANDCONCLUSIONMoreresearchinmakingofphysiologicalscaffoldandminimizingitsreactivity.Abetterquantitativeassessmentforminimizingobservervariation.Betteranimalmodelswithlongerlifespanandfunctionalanalysis.Humantrials

aftergatheringsufficientevidenceofitseffectiveness.Showedsignificantimprovementinthequalityofcartilagetissueandinitshistologicalarrangementbeingmoreregularandlessfibrotic.Itshowsbetteruptakeatthedefectbedandcoalition

withtheadjacentuninjurednormalepitheliumatthejunction.Scaffoldscanbepre-fabricatedandtheir3Dstructureallowsbettermoldingandpreventswashoutofcells.Rigidityallowstransmissionofmechanicalforces

forphenotypemaintenance.Arthroscopictechniquepreventsmorbidity.REFERENCESCimaL.G.,vacantiJ.P.,VacantiC.,IngberD.,MooneyD.AndLangerR.,Tissueengineeringbycelltransplantationusingdegradablepolymersubstrates,JBiomechEng,113,143-51,1991.MahmoudifarN.AndDoranP.M.,Tissueengineeringofhumancartilageinbioreactorsusingsingleandcompositecell-seededscaffolds,Biotechnol.Bioeng.,91,338-355,2005.PetersonL,MinasT,BrittbergM,NilssonA,Sj’’ogren-JanssonE,lindahlA.Twoto(yeareafterautologouschondrocytetransplantationoftheknee.ClinOrthopRelatRes.2000;374:212-34.MinasT.Autologouschondrocyteimplantationinthearthriticknee.Orthopedics.2003;26:945-7.MinasT