Abstract 3697: Cell Sheet Transplantation Improves Damaged Heart Function via More Cell Survival in Comparison With Dissociated Cell Injection
Background: Numerous researchers reported that cell injection improves heart function in animal models and clinical studies. However, cell loss and difficulties in controlling shape and size of grafted cells remains problems. To overcome these problems, we have proposed cell sheet-based regenerative medicine. Although we have confirmed that cell sheet transplantation can recover damaged heart function in several models, quantitative analyses of transplanted cell survival have not been performed. Therefore, cell survival was compared between cell injection and cell sheet transplantation by in vivo bioluminescence imaging.
Methods: Luciferase(+) neonatal rat cardiomyocytes were harvested as cell sheets from temperature-responsive culture dishes. Three cell sheets were layered and transplanted onto infarcted rat hearts (n=8). On the other hand, the same amount of luciferase(+) cardiomyocytes were injected into the myocardium (n=8). Cell survival and functional analyses were performed at 2 and 4 weeks after the implantation.
Results: Cell sheet transplantation constantly yielded greater cell survival than cell injection at 2 and 4 weeks after the transplantation (Fig 1A,B⇓, 4 weeks: cell injection, 1.2±0.9×104 p/s/cm2/sr vs. cell sheet transplantation, 20.1±11.3×104 p/s/cm2/sr). In accordance with cell survival, fractional shortening significantly improved in cell sheet transplantation than cell injection (Fig 1C⇓, 4 weeks: cell injection, 19±2 % vs. cell sheet transplantation, 27±3 %).
Conclusion: Cell sheet transplantation rescued damaged hearts with improved cell survival and should become a promising therapy in cardiovascular regenerative medicine.