A phoenix rises from the ashes of cardiac cell therapy

Stem cell and exosome therapies for regenerating damaged myocardium in heart failure

Finding novel treatments for cardiovascular diseases (CVDs) is a hot topic in medicine; cell-based therapies have reported promising news for controlling dangerous complications of heart disease such as myocardial infarction (MI) and heart failure (HF). Various progenitor/stem cells were tested in various in-vivo, in-vitro, and clinical studies for regeneration or repairing the injured tissue in the myocardial to accelerate the healing. Fetal, adult, embryonic, and induced pluripotent stem cells (iPSC) have revealed the proper potency for cardiac tissue repair. As an essential communicator among cells, exosomes with specific contacts (proteins, lncRNAs, and miRNAs) greatly promote cardiac rehabilitation. Interestingly, stem cell-derived exosomes have more efficiency than stem cell transplantation. Therefore, stem cells induced pluripotent stem cells (iPSCs), embryonic stem cells (ESCs), cardiac stem cells (CDC), and skeletal myoblasts) and their-derived exosomes will probably be considered an alternative therapy for CVDs remedy. In addition, stem cell-derived exosomes have been used in the diagnosis/prognosis of heart diseases. In this review, we explained the advances of stem cells/exosome-based treatment, their beneficial effects, and underlying mechanisms, which will present new insights in the clinical field in the future.

Use of left atrial appendage as an autologous tissue source for epicardial micrograft transplantation during LVAD implantation

We report here the first clinical use of the left atrial appendage (LAA) for epicardial micrograft transplantation during left ventricular assist device (LVAD) implantation. Previously, a sample from the right atrial appendage (RAA) has been available for processing and administering micrograft therapy in cardiac surgery. Both LAA and RAA are rich sources of various types of myocardial cells and are capable of providing both paracrine and cellular support to the failing myocardium. The surgical approach of LAA micrografting facilitates epicardial micrograft therapy dose escalation and treatment of larger myocardial areas than done previously. Moreover, as collection of treated vs. untreated tissues from the recipient heart is possible following LVAD implantation at the time of heart transplantation, the evaluation of the therapy's mechanism of action can be further deciphered at cellular and molecular levels. This LAA modification of the epicardial micrografting technique has the overall potential to facilitate the adoption of cardiac cell therapy during heart surgery.

Dare to dream? Cell-based therapies for heart failure after DREAM-HF: Review and roadmap for future clinical study

Clinical trials of cell-based therapies for heart failure have resulted in significant strides forward in our understanding of the potential the failing heart has for regeneration and repair. Yet, two decades on, the need for novel cell-based therapies for heart failure has never been greater. The DREAM-HF trial, which was presented as a late-breaking trial at the American Heart Association Scientific Sessions 2021 did not meet the primary heart failure outcome, but did show a large, clinically significant reduction in major adverse cardiovascular events (MACE) in patients receiving cells, an effect that was most pronounced in patients with evidence of maladaptive inflammation. These results represent an important step forward in our understanding of how cell-based therapies can exert beneficial effects in patients with heart failure and should serve as a guide for future clinical efforts. In light of the results of DREAM-HF, this review serves to provide an understanding of the current state of cell-based therapies for heart failure, as well as to highlight major knowledge gaps and suggest guiding principles for clinical trials of cell therapy going forward. Using the knowledge gained from DREAM-HF along with the trials that preceded it, the potential for breakthrough cell-based therapies for heart failure in the coming decade is immense.