A team of scientists at the University of Bristol, UK, has developed a synthetic prototissue that is capable of synchronized beating. The team’s work, described in the journal Nature Materials, opens up a route to the fabrication of artificial tissue-like materials capable of collective behaviors, and addresses important challenges in synthetic biology and bioinspired engineering.
Fluorescence optical microscopy image showing emulsion droplets consisting of caged multi-compartmentalized spheroids containing a closely packed mixture of proteinosomes dispersed in oil. Scale bar – 100 μm. Image credit: Gobbo et al, doi: 10.1038/s41563-018-0183-5.
The development of synthetic tissue which can mimic the ability of living cells to produce functions such as beating and chemical detoxification has, until now, remained a major synthetic biology challenge.
University of Bristol’s Professor Stephen Mann and colleagues chemically programmed artificial synthetic cells known as protocells to communicate and interact with each other in a highly coordinated way.
“Our approach to the rational design and fabrication of prototissues bridges an important gap in bottom-up synthetic biology and should also contribute to the development of new bioinspired materials that work at the interface between living tissues and their synthetic counterparts,” Professor Mann said.
The researchers constructed two types of artificial cells each having a protein-polymer membrane but with complementary surface anchoring groups.
They then assembled a mixture of the sticky artificial cells into chemically-linked clusters to produce self-supporting artificial tissue spheroids.
By using a polymer that could expand or contract as the temperature was changed below or above 37 degrees Celsius, it was possible to make the artificial tissues undergo sustained beat-like oscillations in size.
The scientists were able to increase the functionality of the artificial tissues by capturing enzymes within their constituent artificial cells.
Using various combinations of enzymes, they were able to modulate the amplitude of the beating and control the movement of chemical signals in and out of the artificial tissues.
“Our methodology opens up a route from the synthetic construction of individual protocells to the co-assembly and spatial integration of multi-protocellular structures,” said Dr. Pierangelo Gobbo, first author of the study.
“In this way, we can combine the specialization of individual protocell types with the collective properties of the ensemble.”
_____
Pierangelo Gobbo et al. Programmed assembly of synthetic protocells into thermoresponsive prototissues. Nature Materials, published online October 8, 2018; doi: 10.1038/s41563-018-0183-5
