Researchers from the Pohang University of Science and Technology in Korea have developed i 3D heart patches derived from stamina cells. Cardiovascular diseases in fact account for 32% of deaths worldwide. Myocardial infarction plays an important role in heart disease and heart tissue necrosis after the blood supply is decreased or interrupted.
3D bio-printed heart patch technologies loaded with stem cells and their efficacy as a therapeutic and regenerative approach for ischemic cardiomyopathy in reversing scar formation and promoting myocardial regeneration, are being studied with promising results.
The study was published on APL Bioengineering.
3D heart patches: a promising alternative for myocardial repair
“Currently available therapies are not sufficient for the complete treatment of myocardial infarction”, stated the author Jinah Jang. “The development of a new advanced modality is urgently needed, such as the reduction of adverse cardiac remodeling, the promotion of myocardial functions and the correction of molecular or genetic defects.”
Researchers investigated various candidate stem cell types that possess cardiac regenerative potential, explaining their applications and limitations. the research team focused on the challenging implementation of the state-of-the-art 3D bioprinting approach to fabricate 3D cardiac patches and highlight different strategies to implement vascularization and increase cardiac functional properties compared to electrophysiological similarities to native tissue.
Following a myocardial infarction, the tissues and vessels of the myocardium are equally and severely damaged. Therefore, therapeutic or regenerative approaches should be planned to target both at the same time to achieve successful cardiac repair, as the heart has very little ability to regenerate cardiomyocytes or cardiac cells on its own.
The use of 3D bioprinting technology to geometrically control the spatial model and the use of dual stem cell therapy as co-culture can play an important role in promoting and synergistically improving cardiac vascularity and function after myocardial infarction.
The patch-based stem cell therapies that are used today have revealed advanced efficacy, rather than using single component therapies, providing a tissue-friendly environment during the host-graft integration period: “It would be useful to trace the cells of the printed patch to investigate the mode of action of the transplanted patch “, stated the author Sanskrita Das.
“While there are still inherent limitations for clinical study, the suggested stem cell delivery platform technology provides a practical therapeutic perspective for various tissue engineering applications.“, Said the author Hyoryung Nam.
Studies and commitment to cardiac regeneration and science keep moving forward: 3D bio-printed cardiac patches will soon become a possibility to be offered to the patient more and more feasible, practicable and functional, unlocking the barriers to obtain the properties of cardiomyocytes. This will open new frontiers for cardiac research, paving the way for new treatments for patients with cardiovascular disease.
Are there any other methods to heal myocardial scars besides 3D heart patches?
It is estimated that a billion heart cells are lost during a heart attack. Due to the heart attack, the lost tissue is replaced by scar tissue, which can lead to heart failure, arrhythmia and death. In uba research carried out by the experts of theTsukuba University It has been shown how scar tissue cells can be converted into heart muscle cells, effectively regenerating the injured heart.
The injured heart of humans and rodents alike does not have the ability to regenerate after injury. Therefore, the only way for the heart to heal the wound is to build scar tissue in the injured area. Research has always focused on the possibility of reprogramming fibroblasts, the cells that make the connective tissue in a scar, to cardiomyocytes, the working heart muscle cells. The goal of the scientific world is to have the possibility of replacing heart cells, so that even 3D heart patches are not the only alternative, and also preventing heart failure that could lead to a bad course.
Previous research has shown that cardiomyocytes appear to form by directly injecting a harmless virus that carries a series of cardiac transcription factors, proteins that drive the expression of genes that heart muscle cells need for their development and function, into the heart of rodents afterwards. a heart attack. However, the origin and functional significance of these newly formed heart muscle cells have not yet been unambiguously determined.
“Direct cardiac reprogramming has great potential for cardiac regeneration and treatment of myocardial infarctionSays lead author of the study, Professor Masaki Ieda. “However, when transcription factors are introduced, apparent cardiomyocytes can be formed by converting fibroblasts to new cardiomyocytes or by fusing fibroblasts with existing cardiomyocytes. The difference is that only the first process, which we call ‘direct reprogramming’, contributes significantly to regeneration. In this study, our goal was to determine how new cardiomyocytes form when cardiac transcription factors are introduced after myocardial infarction. “
To achieve their goal, i Researchers first generated mice in which all cells glowed red: the guinea pigs were modified so that the fibroblasts glowed green after treatment with the drug tamoxifen. Consequently, when looking at the heart after tamoxifen treatment, the cells that fluoresced both red and green indicated that cell fusion had occurred between fibroblasts and cardiomyocytes. Conversely, the presence of green fluorescence indicated that direct reprogramming of the fibroblasts to cardiomyocytes had occurred.
the researchers, equipped with the necessary technologies, used a mouse model with heart attack and treated the mice with tamoxifen. Although there was no direct reprogramming in a control group, the scientists tracked 1-1.5% of cells reprogrammed directly when a virus carrying cardiac transcription factors was injected into the mice. Both groups showed minimal cell fusion. These results suggest that the primary route to generate new cells in the myocardium with this method is through reprogramming of fibroblasts directly to cardiomyocytes.
“These are amazing results which show that fibroblasts can be reprogrammed directly into cardiomyocytes. Our results demonstrate the exciting potential of direct reprogramming as a strategy for cardiac regeneration after myocardial infarction “concluded Professor Ieda.