Artifical jellyfish created in lab from rat cells

An artificial jellyfish which is able to swim with the help of beating heart muscle cells has been created by scientists.

By Nick Collins, Science Correspondent

The tentacled artificial creature, made from silicon, has been dubbed "Medusoid" because of its resemblance to the snake-haired character from Greek mythology whose gaze turned people to stone.

It is able to mimic the swimming movement of a jellyfish thanks to muscle cells from rat hearts which were implanted onto its silicon frame and grown into a pattern similar to the muscles of a real jellyfish.

By applying an electric current to a container of conducting liquid, the scientists demonstrated they could "shock" the muscles into contracting so that it began to move through the water.

The "reverse-engineering" project by researchers from the California Institute of Technology and Harvard University was published on the website of the Nature Biotechnology journal.

Janna Nawroth, lead author of the study, said that most researchers working in tissue engineering have attempted to copy tissue or organs by simply recreating its major components, regardless of what their function is and whether they could be replaced by something simpler.

She said: "A big goal of our study was to advance tissue engineering. Our idea was that we would make jellyfish functions — swimming and creating feeding currents — as our target and then build a structure based on that information."

Her colleague Prof John Dabiri added: "I'm pleasantly surprised at how close we are getting to matching the natural biological performance, but also that we're seeing ways in which we can probably improve on that natural performance. The process of evolution missed a lot of good solutions."

Jellyfish use a pumping muscle to propel themselves through the water, meaning their movement is based on a mechanism similar to a human heart.

This makes them a useful model for tissue engineering, technology which could one day be used to create synthetic hearts or other organs for human patients.

Prof Kevin Kit Parker, one of the study's authors, said: "I saw a jellyfish at the New England Aquarium, and I immediately noted both similarities and differences between how the jellyfish pumps and the human heart. The similarities help reveal what you need to do to design a bio-inspired pump.

"The jellyfish provides a design algorithm for reverse engineering an organ's function."

Prof Dabiri added: "A lot of work these days is done to engineer molecules, but there is much less effort to engineer organisms.

"I think this is a good glimpse into the future of re-engineering entire organisms for the purposes of advancing biomedical technology."