The Role Of Bone Marrow Derived Mesenchymal Stem Cells In Repair Of Acute Skin Irradiation Injury

Part one:Isolate and culture Fetal the bone marrow-derived mesenchymal stem cells-basic and biological charactersObjective:To explore the condition of the isolation and culture of fetal bone marrow-derived mesenchymal stem cells(FMSCs) in vitro and to observe the biological characteristics of FMSCs.To establish a steady culture system of FMSCs.Methods:Bone marrow mononuclear cells(BMMNCs) were harvested from bone marrow by flushing femurs and tibias of four-month old human fetales.The resulting cells were purified via density gradient centrifugation and cultured in vitro.The proliferation and growth characteristics of FMSCs were analyzed during primary and passage cultures. FMSCs cell growth curve and divisional index curve was detected by MTT.Results:After seeded 2 days,the adherent cell showed spindle shape,polygonal shape and fibroblast-cell-like shape.FMSCs was passaged after one week,the FMSCs were still in latent phase after being passaged 24-36 hours,2-3 days later,cells were in log phase,6 days later,and cells came into platform phase.Until 15 passages,the growth rate of FMSCs decreased.The phenotype analysis with FMC showed that FMSCs expressed highly CD29,CD44 and CD49e.They also expressed low level of CD106,CD54,CD11b, but FMSCs did not express CD34.Conclusion:FMSCs isolated,cultured,proliferated applying density gradient centrifugation,attachment method combining with monoclone cultivation have high autoploidy,. Part two:Bone Marrow Derived Mesenchymal Stem CellsPromoted the Regeneration of Acute Skin Irradiation InjuryObjective.To explore the role of bone marrow derived mesenchymal stem cells(MSCs) on repair of skin irradiation injury.Methods:The 46 mice were randomly grouped as follows:the experimental group(n=20),the control group(n=20) and the remains without any disposal.The mice models with local acute skin irradiation injury were established by 40Gy irradiation with accelerator(Elekta SL-18) on the haunch of mice.MSCs were directly transplanted into mice of experimental groupa as soon as the irradiation process was finished.The wound healing rate and the number of blood capillary in wound skins were measured.To observe the pathological changes of injured skin and the migration of MSCs in skin and other various tissues in order to explain the effects of MSCs in promoting the repair of wound and its mechanism.Results:The mice transplanted xenogenic MSCs showed better and faster in wound healing,the healing time moved up 4-6 days.It appears that the degree of damage in epidermis,hair follicle and so on was significantly less in experimental group than those in control group.MSCs distributed widely in injured skin and multiple organs.Conclusion:MSCs promoted the regeneration of acute skin irradiation injury, which might contribute the interaction between MSCs and wound microenviroment.