In a study published today in Nature, researchers from the Institute for Bioengineering of Catalonia (IBEC) at PCB and the Universitat Politècnica de Catalunya (UPC) report a new physical property of cells  that may explain the unusual ability of cells to undergo extreme deformations without breaking. The research could help us build better artificial organs or new bionic technologies such as organs-on-a-chip.

A team –led by Marino Arroyo, professor at the Polytechnic University of Catalonia and Associated Researcher at IBEC, and Xavier Trepat, IBEC group leader and ICREA research professor– developed a new approach to subject epithelial tissues– the thin cellular layers that cover internal and external surfaces of the body – to very large deformations, up to four times their original size. These cellular layers are fundamental to life, as they protect the body from radiation, pollutants and pathogens. They’re also responsible for gas exchange in the lungs, absorption of nutrients in the gut, and excretion of urine in the kidneys.

The researchers found that the epithelial sheets have a different and unusual mechanical behavior. To their surprise, tissues did not break during stretching, and they were able to recover their initial size in a fully reversible way when unstretched. Even more surprisingly, some cells in the tissue barely stretched, while others became ‘superstretched’, increasing their area more than ten times.

The authors identified the molecular mechanisms that explain this physical behavior, which they call ‘Active superelasticity’ as an analogy with the behavior of some high-tech metal alloys used in medical technologies. As cells become stretched, they become equally happy in an unstretched state or in a super-stretched state. As a result, these cell sheets can deal with increasing stretch by progressively switching cells into their super-stretched state without increasing tension, which would otherwise compromise integrity or cohesion. Ernest Latorre of IBEC’s Integrative Cell and Tissue Dynamics group is the first author of the study.

► For further information: IBEC website  [+]

► Reference article:
Ernest Latorre, Sohan Kale, Laura Casares, Manuel Gomez-Gonzalez, Marina Uroz, Léo Valon, Roshna V. Nair, Elena Garreta, Nuria Montserrat, Aránzazu del Campo, Benoit Ladoux, Marino Arroyo & Xavier Trepat (2018). “Active superelasticity in three-dimensional epithelia of controlled shape“. Nature (2018). DOI: 10.1038/s41586-018-0671-4