Research On Autologous Skeletal Myoblast Cardiomyoplasty

Objective: In order to test the hypothesis that skeletal muscle satellite cells (SCs)which were isolated from skeletal muscle, cultured and proliferated in vitro, andtransplanted into myocardial infarction areas in different time after acute myocardialinfarction by different ways could differentiate into cardiac-like muscle fibers and thusrepaired damaged heart muscle.Methods: Six adult mongrel dogs of either sex were divided into two groupsrandomly. Each group contains 3 dogs. With the introduction of Prof Chiu's techniques,Satellite cells (SCs) were isolated from skeletal muscle. Density centrifugation was usedto purify the obtained cell pellets. Retrieved SCs were counted and their viability wasassessed by trypan blue exclusion test. After 10-14 days, When the number of Satellitecells cultured in vitro achieved 5-6 ×10~7, the SCs labeled with DAPI for 12 hour werecollected and resuspended in 5-6ml of M199. The same donor dog of SCs served astheir recipient. Left lateral thoracotomy was performed under General anesthesia.Myocardial infarction area I on free wall of left ventricular was made by combinedmethods of coronary ligation and C-shape cryoinjury. Myocardial infarction area II wasmade by pure cryoinjury near myocardial infarction (MI) area I. Group A: The collectedSCs were implanted into two MI areas by intracoronary artery and direct injectionrespectively in acute myocardial infarction period. Group B: SCs primary culture andMI model were made at the same time. After 10-14 days, the collected SCs (5-6 ×10~7)was implanted into tow MI area at the same way as that of group A under secondthoracotomy in subacute myocardial infarction period. After 4 weeks implantation,Dogs were sacrificed and the target myocardial tissue were processed for histologicalexamination.Results: (1) SCs were isolated successfully Cell viability ranged from 70%-80%,purity>95%. Reducing serum concentration in growth medium and delaying passage,the SCs commenced the fusion process that resulted in formation of multincleatedmyotubes. Immunohistochemistry (IHC) demonstrated its origin from skeletal muscle.(2) Small area of MI could be made by combined methods of coronary ligation and C-shape cryoinjury or by pure cryoinjury successfully (3) There was discrete fluorescentin MI area I of group A with fluorescent microscope, however, few fluorescent wasseen in MI area I of grOU B. Line-shaped fluorscent was found in MI area II of bothgrouP wh lluorescent microscoPe. Further examination of above resufls with lighndcroscoPe, no cardiac-like striatCd muscle fibers wer foUn.ConclusiOn: According tO the present research in the worid and this eXPdrientalStUdy cellular cardomyoPasty wh satel1ite cell imPlanaton is unsuccessAn.Progressive research muSt be done in the fube.