The Study On Transplantation Using Cells Derived From Embryonic Stem Cells For Mouse Spinal Cord Complete Transection Models

Backgroud: More and more researchers are focusing their eyes on the studyon spinal cord injury (SCI) because SCI has a high disability rate and treatment ofSCI has puzzled researchers for a long time. It is very important to find a availabletreatment of SCI for society and family. Howere, the restoration of SCI has been ahuge task for the human being and no available therapeutic methods has beenfound till now so that trying to find an ideal method is the common goal formedical staffs. SCI causes the loss of local nerve cells and interruption of descending andascending tract. The interruption of descending and ascending tract inducesdysfunction in the lower damaged-level without the regulating and dominatingfrom the brain and then induces the severe symptoms such as paraplegia.Because SCI can't significantly regenerate, surgery cannot cure it and thebetter method is to replace the damaged neurons through transplant. Theresearchers have been undertaking lots of tissular and celluar transplantexperiments The results were significant to some extent but the clinicalapplication was inhibited due to the implants sources were limited and there weresome immuno-rejection from tissues implants. Now, many researchers sduay adult stem cell to treat SCI in lab. But with thediscovery of embryonic stem cells (ESCs) and development of in-vitro culturetechniques in recent years, Researchers have know that it can keepself-reproduction ability and multi-directional differentiation potential after goingdown to posterity repeatedly. ESCs have been already cultivated in vitro and cellsderived from ESCs posses characteristics of neural precursor cell (NPC). ESCstransplantation for stimulating nerve cells regeneration, recovery and restoration,have been emphasis in the foundation study of spinal cord diseases and newwishes for clinical treatment in SCI.ESCs are pluripotent cell lines established from embryonic cellscharacterized nearly unlimited self-renewal and differentiation capacity. Duringdifferentiation in vitro, ES cells were found to be able to develop into specializedsomatic cells types and to recapitulate processes of early embryonic development.These properties allow to use ES cells as model system for studying earlyembryonic development by gain-or loss-of-function approaches, or to investigatethe effects of drugs and environmental factors on differentiation and cell functionin embryotoxicity and pharmacology. Now, human ESC may be used for thegeneration of somatic precursor or differentiated cells and tissue therapy.In order to grasp all characteristics of ESCs and supply clinic research infuture, we did some work of study s8 line of mouse ESCs (take marker geneLac-Z). After we induced ESCs to NPCs using direct methed and checked it invitro, we transplanted cells derived from ESCs and observed survival andmigration and split using morphologic method and observed mouse neuralfunction recovery using ethology methed.The present experiments of stem cell for SCI are more concentrated on thestudies of spinal cord hemitransection or contusion and fewer on completetransection, and the direct evidences in recovering neural pathway of spinal cordand brain, especially in recovering cortico spinal tract to restore movementfunctions of limbs were not enough in morphology and quite few in gene, so theeffects and mechanism of ESCs on spinal cord transaction need further study.Chapterâ…  cellullar inductionObjectives. To observe vegetation condition of cells derived from s8 line ofESCs and analyse characteristics of cells derived from ESCs.Methods. To observe cell morphous after serial subcultivation in culturefluid containing MEF cells and LIF. After serial subcultivation reduce cell usingfluid containing ATRA and removing LIF in 5days.Cells is cultured in culturefluid and is differentiated to cells possessing characteristics of NPCs.We observeNestin and MAP-2 and GFAP by RT-PCR.Results. ESCs keep self-reproduction ability in culture fluid containing MEFand LIF.After reduced in vitro cells began differentiation and expressed Nestinand MAP-2 but did not express GFAP.Conclusions. ESCs can keep self-reproduction ability and multi-directionaldifferentiation potential after going down to posterity repeatedly in culture fluidcontaining MEF and LIF.Cells derived from ESCs expressed Nestin and MAP-2successfully. Cells derived from ESCs posses characteristics of division growthand passage.Chapterâ…¡ cellular transplantationObjectives. To transplanted cells derived from ESCs and observed survivaland migration and split in vivo using morphologic method and observed mouseneural function recovery using ethology methed.we investigate the effect andmechanisms after cellular transplantation.Methods. In C57/BL6J mouse, age8weeks, T9 spinous processes as central,spinal cord was completely cut by blade to form the model. ES cell-derived cellswere planted into vertebral canal around injured spinal cord, and different controlgroups were set. Experimental mouse were observed functionally and structurallyfor regeneration of spinal cord by many means: routine frozen section, tissue andstructure of transplanted region observed with light microscope. Ectogenesis cellsexistence tested by enzyme logy and immuneohistological technique and thenbehavioral observation performed including slanting board tests, BBB score, et al;the survival differentiation migration and effect infunction recovery in the focalinjured spinal cord. Also to establish an effective treating method on injured spinalcord.Results. ES cell-derived cells could survive in the injured region and migratea long distance to injured region and differentiate into neurons, glial andcommunications with damaged spinal cord tissue. Motor function of model wasimproved notably.Conclusions. Cells derived ESCs can long-term surviveand and immigaratewith self-differentiation in vivo of host. That cells derived from ESCs cansubstitute damaged neuron and glia cells is confirmed. Meanwhile, that motorfunction of model is improved is confirmed after cellular transplantation.