Artificial jellyfish could advance human tissue engineering

Researchers in the US have created an artificial jellyfish in a project to help scientists improve the reverse engineering of human muscles.

A team from Harvard University and the California Institute of Technology (Caltech) used inanimate silicone and living heart tissues from a rat to recreate a medusa jellyfish by studying and mimicking its cellular structure.

Applying this process to human muscle tissue could enable scientists to better engineer artificial organs.

‘As engineers, we are very comfortable with building things out of steel, copper and concrete,’ said Harvard’s Kevin Kit Parker, co-author of a paper on the research published in the journal Nature Biotechnology.

‘I think of cells as another kind of building substrate, but we need rigorous quantitative design specs to move tissue engineering to a reproducible type of engineering.

‘The jellyfish provides a design algorithm for reverse engineering an organ’s function and developing quantitative design and performance specifications. We can complete the full exercise of the engineer’s design process: design, build and test.’

To create the jellyfish, dubbed ‘Medusoid’, the researchers used analysis tools designed for studying biometrics and crystallography to make maps of the alignment of subcellular protein networks within all of the animal’s muscle cells.

They also studied how the jellyfish moves through the water, including how its muscles are triggered by electric signals within its body.

Having discovered that a sheet of cultured rat heart muscle tissue would react to electric simulation in a liquid environment, they used this material together with silicone polymer to create a thin membrane that resembles a small jellyfish with eight arm-like appendages.

They used the same analysis tools to quantitatively match the subcellular, cellular and supracellular architecture of the jellyfish muscles with the rat heart muscle cells.

The jellyfish was then placed in a container of ocean-like salt water and shocked into swimming with synchronised muscle contractions that mimic those of real jellyfish.

‘A big goal of our study was to advance tissue engineering,’ said Janna Nawroth, a doctoral student from Caltech and lead author of the study.

‘In many ways, it is still a very qualitative art, with people trying to copy a tissue or organ just based on what they think is important or what they see as the major components — without necessarily understanding if those components are relevant to the desired function or without analysing first how different materials could be used.’

The researchers now aim 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 and replicate more advanced behaviours such as heading towards a light source and seeking energy or food.