A team of Spanish researchers have demonstrated promising results in regenerating cardiac tissue using three-dimensional engineered patches made from a mixture of fibrin and mesenchymal stem cells (MSCs). It is hoped that the cells, derived from human umbilical cord blood, could induce recovery of cardiac function and potentially ease the strain on heart transplantation – currently the only curative treatment for heart failure.
The study, published online ahead of print in Stem Cells Translational Medicine, builds on previous work involving less sophisticated methods of stem cell delivery, such as injections and intravenous administration. Regarding these therapies, lead author of the study and Professor at Universitat Autònoma de Barcelona (Barcelona, Spain), Antoni Bayes-Genis, said, “While feasible and safe, the treatments exhibited only modest benefits.”
“The survival rate of the implanted stem cells was generally low and about 90% of them either died or migrated away from the implantation site, generally to the liver,” added the study’s first author, Santiago Roura, member of the Heart Failure and Cardiac Regeneration Research Program at Germans Trias i Pujol Health Science Research Institute (Barcelona, Spain). “These limited effects are probably due to the adverse mechanical stress and hypoxic conditions present in the myocardium after the heart attack.”
Several scaffolds have been found to be suboptimal. Fibrin was chosen by the team owing to its ability to act like biocompatible ‘glue’, not only holding cells at the site of injury but also stimulating angiogenesis. The patches with MSCs were tested in a mouse model of myocardial infarction. The patches adhered well and the MSCs proliferated and began to differentiate, as seen through bioluminescence – the MSCs had been modified to coexpress luciferase and florescent protein reporters. Angiogenesis was also demonstrated. The patches were connected both to the subjacent heart tissue and surrounding microvasculature.
“As a result, the heart function in this group of mice was better than that of the animals in either of the other control groups,” explained Bayes-Genis. Indeed, Echocardiography revealed that left ventricular ejection fraction was improved compared with mice harbouring just fibrin patches alone without stem cells and control mice. Therefore, the authors concluded that these patches infused with umbilical cord blood MSCs attenuated infarct-derived cardiac dysfunction when transplanted over damaged heart tissue. Bayes-Genis concluded, “This study provides promising findings for the use of umbilical cord-blood MSCs and fibrin patches in cardiac repair.”
Sources: Roura S, Soler-Botija C, Bagó J et al. Postinfarction Functional Recovery Driven by a Three-Dimensional Engineered Fibrin Patch Composed of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells. Stem Cells Translational Medicine, doi:10.5966/sctm.2014-0259; Fibrin and Stem Cell Patches Show Promise for Heart Healing, http://stemcellsportal.com/fibrin-and-stem-cell-patches-show-promise-heart-healing