Growing heart cells could aid heart disease research
Johns Hopkins researchers successfully grew mature and healthy heart muscle cells using human stem cells by implanting the stem cells from a healthy adult into newborn rats.
By using animal hearts to grow heart muscle cells, researchers are able to implant the biological signals and chemistry that is needed for immature heart muscle cells to grow beyond what generally stunts them in culture dishes.
Previously, growing heart muscle cells never made it out of the newborn stage, even after leaving them to grow in a dish for a year. The newborn heart cells are generally smaller and have low pumping force, making them the least ideal for an accurate depiction of the biology and chemistry of adult heart tissue, which is usually what is affected by heart muscle diseases.
The researchers hope that this method will aid studies of how heart disease develops, as well as the development of new diagnostic tools and treatment.
“Our concept of using a live animal host to enable maturation of cardiomyocytes can be expanded to other areas of stem cell research and really opens up a new avenue to getting stem cells to mature,” said Chulan Kwon, PhD, associate professor of medicine, member of the Johns Hopkins University School of Medicine’s Institute for Cell Engineering and leader of the study, in a press release.
The researchers created a cell line of immature heart cells that they took from mouse embryonic stem cells and tagged them with a fluorescent protein. They injected 200,000 cells into the lower chamber of the newborn rat hearts.
The fluorescent cells appeared as adult heart muscle cells with elongated and striped patterns after a month. They compared 312 genes in the grown cells in the heart to the genes of immature heart and adult heart muscle cells. The grown cells were more genetically similar to adult heart muscle cells and beat like a normal adult heart.