Transplantation of Human Embryonic Stem Cell-derived CD15+ Isl-1+ Progenitors in Severe Heart Failure

Heart failure due to coronary artery disease is a major problem because of its high prevalence, increased incidence and associated costs. When conventional medical/interventional treatments fail and if cardiac transplantation is contra-indicated, alternate options need to be considered. Transplantation of stem cells has emerged as one of them. While the optimal cell type still remains debatable, there is compelling evidence that cells whose phenotype closely matches that of the recipient tissue look sound candidates. In this context, human embryonic stem cells are attractive because of the possibility to drive their fate in vitro, prior to transplantation, towards a cardiac phenotype. We have developed a process for achieving such a commitment and generating cardiac-directed cells. The objective of this study is to assess both the feasibility and safety of this approach. In addition, the disadvantages of multiple intramyocardial injections have now been recognized. We have then taken advantage of the surgical setting of the trial (which entails concomitant coronary artery bypass or a mitral valve procedure) to switch from injections to the epicardial delivery of a fibrin gel into which the progenitor cells have been embedded. Coverage of this cell-loaded patch by an autologous pericardial flap is finally designed to provide trophic factors to the underlying cellular graft with the hope of improving its viability.