Harvard University researchers have created a new "biohybrid" fish that swims independently by using human heart cells to mimic the physics of a pumping heart.
This odd synthetic fish scoots along in its salt and glucose solution, its tail flicking repeatedly from side to side, using the same power as our beating hearts.
This ingenious tiny circulatory system can swim to the beat for over 100 days.
"My interest is in pediatric heart disease," Kit Parker, a Harvard bioengineer and a lead researcher of the project, told The Daily Beast. "I want to build a tissue-engineered heart for a sick kid born with a malformed heart. But I can't put that heart into a living child without having ever tested it myself."
Parker discovered a means to test this by creating marine biohybrids that can demonstrate whether a culture of altered heart cells can truly beat and operate like a natural heart.
"Biohybrid" refers to a combination of live cells and synthetic materials, which are made of living components but act in a similar way to a gadget or new technology.
The construction of the biohybrid fish is based on two major regulatory aspects of our hearts: their ability to function without conscious input (automaticity) and messages activated by mechanical motion (mechanoelectrical signaling).
Researchers will hopefully be able to explore these elements of heart disease more closely as a result of the research's findings.
It's critical to demonstrate that it's possible to create human heart tissue that can beat on its own because the body can't restore cardiac cells lost to disease or inflammation.
While constructing anything that looks like a heart is simple, making something that truly behaves like one is a much more difficult issue. The wiggling fishbot is a significant step forward, drawing on prior studies that used rat heart muscles to construct a jellyfish biohybrid pump and a cyborg stingray.
Parker's lab created a stingray powered by rodent heart cells in 2016. They utilized light to manipulate the cells, causing the robot's fins to undulate and drive it through the water. His team employed stem cell technologies to turn human skin cells into heart muscle this time.
"The really interesting thing about these fish, which we weren't expecting, is how long they would swim and how fast they would swim in the dish," Parker said.
He says that heart cells maintain their health by constantly rebuilding themselves, a process that takes roughly 20 days. He says that because the fish swam for more than 100 days, "each cell in there has rebuilt itself about five times."
Muscle cells, like those in the human heart, grew stronger with exercise. This means that the cells could be used to mend a failing heart in the future.
This research was published in Science.
