Abstract 11848: Transplantation of Cell Sheets with Human iPS Cell-derived Cardiomyocytes and Vascular Cells for Infarcted Hearts: A Basic Study
BACKGROUNDS: To realize cardiac regeneration using human induced pluripotent stem cells (hiPSCs), efficient differentiation from hiPSCs to defined cardiac populations (cardiomyocytes [CMs]/ endothelial cells [ECs]/ vascular mural cells [MCs]), and transplantation technique for fair engraftment are required. Recently, we reported that mouse ES cell-derived cardiac cell sheet transplantation to rat myocardial infarction (MI) model ameliorated cardiac dysfunction (Stem Cells, 2012). Here we tried to extend this strategy to hiPSCs.
METHODS & RESULTS: We have reported an efficient CM differentiation protocol from hiPSCs based on a monolayer culture (PLoS One, 2011), in which cardiac troponin-T (cTnT)-positive CMs robustly appeared (50-80%). In this study, we further modified the protocol to induce vascular cells (ECs/MCs) together with CMs by vascular endothelial cell growth factor supplementation, resulted in proportional differentiation of cTnT+-CMs (60.6±12.4% of total cells), VE-cadherin+-ECs (7.7±4.7%) and PDGFRb+-MCs (17.7±11.2%) at differentiation day 15 (n=15). Then, these cells were transferred onto temperature-responsive culture dishes (UpCell; CellSeed, Tokyo, Japan) to form cardiac cell sheets with defined cardiac populations. After 4 days of culture, we successfully collected self-pulsating cardiac cell sheets with 7.6×105±2.6 (n=15) of cells containing CMs (48.8±14.6% of total cells), ECs (3.9±3.5%), and MCs (23.3±17.2%). The cell sheets were transplanted to a MI athymic rat heart one-week after MI. In transplantation group, echocardiogram showed a significant improvement of systolic function of left ventricle (fractional shortening: 22.5±4.8 vs 36.2±7.8%, p<0.001, n=24) and a decrease in akinetic length (20.6±9.3 vs 2.1±7.0%, p<0.001, n=24) (pre-treatment vs 4weeks after transplantation). We confirmed a prominent accumulation of vWF-positive endogenous ECs around the graft within three days after transplantation, indicating angiogenic effects of the sheet.
CONCLUTIONS: Transplantation of cell sheets with hiPSC-derived defined cardiac populations ameliorates cardiac dysfunction after MI. Thus, we developed a valuable technological basis for hiPSC-based cardiac cell therapy.
- © 2012 by American Heart Association, Inc.