Gene therapy instead of a pacemaker
Cardiologists from Cedars Sinai Medical Center, working under the guidance of Dr. Eduardo Marban, have developed a minimally invasive gene therapy approach that allows turning non-specialized heart cells into a "biological rhythm driver" that ensures stable myocardial contraction.
As part of the study, scientists conducted experiments on a pig model of complete heart block (a year and a half ago they tested this technique on guinea pigs). An adenoviral vector carrying the TBX18 gene (T-box 18), which is an embryonic transcription factor that triggers the transformation of cardiomyocytes into cells generating electrical impulses necessary to maintain rhythmic contraction of the heart muscle, was injected into the heart of animals using a catheter.
On the second day after the procedure, the heart rate of the animals significantly increased, which was not observed in the control group pigs that were not subjected to gene therapy. This effect persisted throughout the entire follow-up period of 14 days, and provided a better ability of the heart to maintain physical activity.
When analyzing the heart tissue of experimental group animals in the area of administration of the gene therapy drug, cells with morphology characteristic of pulse-generating cells of the sinus-atrial node were identified.
It is also important that no manifestations of local or systemic toxicity were recorded in animals.
According to the authors, it was initially assumed that the biological pacemaker would be used as a temporary measure to maintain the heartbeat of patients with infection of the implantation zone of a traditional mechanical pacemaker. However, the results obtained indicate that further improvement of the technique will allow the development of a therapeutic approach that provides a long-term result.
Moreover, the developers suggested that in the long term, the introduction of a gene therapy vector through a catheter will save the lives of unborn children with congenital heart block. They hope that the first version of the developed approach will be ready for clinical trials in 3 years.
Article by Yu-Feng Hu et al. Biological pacemaker created by minimally invasive somatic reprogramming in pigs with complete heart block is published in the journal Science Translational Medicine.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on Cedars-Sinai materials:
Transplanting gene into injured hearts creates biological pacemakers.
18.07.2014