Researchers at Harvard University and the California Institute of Technology say the successful effort was a proof of concept for reverse engineering a variety of muscular organs and simple life forms.
A description of the research that led to the tissue-engineered jellyfish, dubbed "Medusoid," has been published in Nature Biotechnology.
Jellyfish propel themselves through the water by pumping, in an action similar to the way a human heart pumps blood through the body, researchers said.
"It occurred to me in 2007 that we might have failed to understand the fundamental laws of muscular pumps," Kit Parker, a Harvard professor of bioengineering, said.
"I started looking at marine organisms that pump to survive. Then I saw a jellyfish at the New England Aquarium and I immediately noted both similarities and differences between how the jellyfish and the human heart pump."
Researchers used a sheet of cultured rat heart muscle tissue that would contract when electrically stimulated in a liquid environment to create an ersatz jellyfish.
The artificial construct was placed in container of ocean-like salt water and shocked into swimming with synchronized muscle contractions that mimic those of real jellyfish.
"I was surprised that with relatively few components -- a silicone base and cells that we arranged -- we were able to reproduce some pretty complex swimming and feeding behaviors that you see in biological jellyfish," said John Dabiri, a Caltech professor of aeronautics and bioengineering.
The researchers said they hope to further evolve the artificial jellyfish, allowing it to turn and move in a particular direction, and even incorporating a simple "brain" so it can respond to its environment.