Researchers have used stem cells to create a lab-grown human heart tissue which actually beats. Created by scientists from University Medical Center Hamburg-Eppendorf in Germany, the heart tissue also expresses genes and responds to drugs in the same way as a real human atrium, the upper chamber in the heart through which blood enters. The hope is that the lab-grown tissue could prove useful for investigating new treatments for atrial fibrillation, a heart condition that causes irregular heartbeats. Atrial fibrillation affects more than 33 million people around the world.
“The principle technique to make 3D heart muscles from suspended heart cells was already developed by me 24 years ago,” Professor Thomas Eschenhagen, one of the lead researchers in the project, told Digital Trends. “At that time, we used embryonic chicken heart cells.”
Since then, Eschenhagen and his fellow researchers have optimized the technique and applied it to rat, mouse and, eventually, human cells. Unlike standard 2D cell culture, the stem-cell-derived tissues created in this latest study were made to form a three-dimensional structure. This builds on the 2012 Nobel Prize-winning work of Dr. Shinya Yamanaka and John Gurdon, who showed that induced pluripotent stem cells (hiPSCs) can be made from any type of human somatic cells, such as those taken from a skin biopsy. As a result, Eschenhagen said that 3D beating heart muscles can be easily created in a dish in numbers conceivably in the hundreds of millions.
Don’t expect this to be the start of complete lab-grown hearts, however — at least, not according to Eschenhagen. “I personally do not think that making of an entire new heart in the dish [or] bioreactor is a realistic and useful goal,” he said. “Such an artificial heart would need to be perfect already at time of transplantation to replace the diseased heart. That’s very unlikely given the size and the complexity of a heart, including blood vessels and valves.”
Instead, Eschenhagen said that the team are working on a different strategy to improve heart function after a heart attack. This would involve suturing patches containing progenitor cells or cardiomyocytes onto injured hearts for carrying out cardiac repair. This has already been demonstrated in rats and guinea pigs. At present, Eschenhagen said that the team is investigating carrying out something similar with pigs, before preparing for the first human trials. These should take place in the “foreseeable future.”
A paper describing the work was recently published in the journal Stem Cell Reports.