The first trials were carried out twenty years ago, in animals with stem cells in the heart the latest experimentation with satisfactory results in mice was made last year (read HERE). The aim has been to regenerate lost heart muscle to recover function after a heart attack. Strategies using adult stem cells have not shown efficacy in patients, despite positive preclinical experiments in animal models. In the article published in Science Perspective, Murry and MacLellan (February 21, 2020) discuss the reasons underlying this lack of success in the clinic, including lack of stem cell engraftment and survival. One more example that the results of research in animals are not always applicable to humans (read HERE).

The authors concluded that new heart cell therapy strategies are needed. An emerging strategy to overcome these problems is the use of pluripotent stem cells, which have demonstrated long-term engraftment and regeneration in preclinical studies. The authors discuss the future hurdles that need to be overcome to successfully develop this cell therapy (Science February 21, 2020: Vol. 367, Issue 6480, pp. 864).

Cell therapy research. iPS cells appear to be the best option

Another study published in Rambam Maimonides Med J. (April 29, 2020) confirms that iPS cells are a good line of research because they have not ethical problems and some experimentation in humans has achieved good results. The author says “A major concern when using iPS cells, is tumorigenesis. However, this risk can be mitigated by isolating cells or cell lines that have undergone at least some differentiation. An initial clinical trial to evaluate the safety and efficacy of a patch with 100 million reprogrammed iPSC cardiomyocytes was approved in Japan. Three patients with ICM were treated initially; a further 7–10 patients will be recruited and followed up over the period of 1 year. The Treating Heart Failure With hPSC-CMs (HEAL-CHF) Trial (NCT03763136) is an open-label study recruiting 5 patients to receive epicardial injection of allogeneic PSC-CMs. There are as yet no reports from either of these two studies. Continuing studies will have to investigate methods to maintain stable cell lines as well as address scalability for clinical-grade production (read more HERE)”.

These new lines of research have a hopeful future without ethical problems.