Three-dimensional "patch" for the heart
A group of researchers working under the guidance of specialists from the University of Minnesota, using the method of three-dimensional bioprinting, created a revolutionary three-dimensional patch that promotes the restoration of damaged heart tissue after myocardial infarction.
According to statistics, heart diseases, including myocardial infarction, are the leading cause of death worldwide. In myocardial infarction, cardiac muscle cells die due to impaired blood flow. The human body is not able to replace the dead cardiomyocytes, therefore, scar tissue is formed at the site of damage that is not capable of reducing, which automatically places the patient in an increased risk group for cardiac dysfunction and the development of heart failure.
The authors have developed a bioengineered "patch" to repair such damage. To do this, they used the method of three-dimensional bioprinting to incorporate human cells into a framework of gelatin-methacrylate gel. To form a full-fledged muscle tissue, the skeleton was populated with a mixture of cells (cardiomyocytes, smooth muscle and endothelial cells in a ratio of 2:1:1) obtained from human induced pluripotent stem cells (iPSCs).
Created with the help of 3D printing "patch" on the background of a mouse heart
Already during the first day after the settlement of the skeleton, these cells began to form calcium potentials and synchronously contract. At the same time, the frequency of phase changes of contraction and relaxation, as well as the peak amplitude of the calcium potential increased significantly over the next 7 days.
When implanting a cell-seeded "patch" into the heart injury zone of a mouse model of myocardial infarction, researchers observed a significant increase in the functional ability of the heart within four weeks after implantation. In addition to improving cardiac function in animals of the experimental group, compared with animals of the control group, there was an improvement in such indicators as the size of the infarction zone, the level of cell apoptosis, the density of the vascular network, the number of arterioles and the rate of cell proliferation. At the same time, the biocompatibility of the frame ensured its complete dissolution in the body.
The authors note that the fundamental difference between their development and the earlier ones is that the frame they created is a three-dimensional structural copy of the heart tissue, the stencil for the creation of which was obtained by digital three-dimensional scanning of a tissue sample. They are currently working on creating a larger "patch" that will be tested on a pig heart, the size of which is comparable to the size of a human heart.
Article by Ling Gao et al. Myocardial Tissue Engineering With Cells Derived From Human-Induced Pluripotent Stem Cells and a Native-Like, High-Resolution, 3-Dimensionally Printed Scaffold is published in the journal Circulation Research.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the University of Minnesota: 3D-printed patch can help mend a broken heart
19.04.2017