Toward Biological Pacing by Cellular Delivery of Hcn2/SkM1

Electronic pacemakers still face major shortcomings that are largely intrinsic to their hardware-based design. Radical improvements can potentially be generated by gene or cell therapy-based biological pacemakers. Our previous work identified adenoviral transfer of Hcn2 and SkM1, encoding a “funny current” skeletal fast sodium current, respectively, as potent combination induce short-term pacing in dogs with atrioventricular block. To achieve long-term pacemaker activity, alternative delivery platforms need explored optimized. The aim the present study was therefore investigate functional Hcn2/SkM1 via human cardiomyocyte progenitor cells (CPCs). Nucleofection SkM1 CPCs optimized determined for vitro . modified were analyzed using patch-clamp validation characterization transgene expression. In addition, biophysical properties further investigated lentivirally transduced analysis. compare both modification methods vivo , nucleofected GFP injected left ventricle male NOD-SCID mice. After 1 week, hearts collected expression engraftment. Subsequent studies carried out computational modeling. Both nucleofection lentiviral transduction resulted channels. However, more efficient than nucleofection-mediated virally survived better These data support future use over nucleofection, concerning CPC-based cardiac delivery. Detailed revealed Skm1 current kinetics within range previously reported values other systems. Finally, modeling indicated CPC-mediated generate stable function ventricular myocytes. illustrated plays an essential role final stage diastolic depolarization, thereby enhancing functioning delivered Hcn2. Altogether these development testing bradycardia models.