Mimicking the ‘stretch and squidge’ in the human body the future of tissue engineering

17 Sep 2020

Five of the world’s finest tissue engineering experts, including Professor Justin Cooper-White from The University of Queensland, have come together to present the latest research from their field in the prestigious scientific journal, Nature.

Along with Professor Cooper-White, researchers from Stanford University, Harvard University and University of Pennsylvania have reviewed the works investigating how the viscoelasticity of our extracellular matrix, the mixture of proteins and sugar-like molecules that surround the cells (and stem cells) in our tissues, impacts on cell behaviours.

“Viscoelasticity describes the way materials, like our skin, muscles, bones or even our organs, respond to being ‘stressed’, through pushing, pulling or shearing; forces that our tissues experience in everyday life,” Professor Cooper-White said.

“All tissues in the body are viscoelastic – it is an intrinsic property of them.

“The concept of tissue and extracellular matrix viscoelasticity, and how it changes with age or the onset of disease, is fundamental to our understanding of how cells modify their behaviours when impacted by many diseases, such as cardiovascular disease, osteoarthritis, or even cancer.

“It even affects how cells respond to drug treatments and how stem cells — the cells responsible for repairing our tissues if damaged — change, multiply or die.

“Cells respond to the viscoelasticity of their surrounding extracellular matrices through a process called ‘mechano-transduction’; just like the way in which when you grab hold of something with your hand, your sensory and nervous system connected to it tells your brain that it is ‘hard and stiff’ or ‘soft and squidgy’ or ‘soft and stretchy’!”   

Since Professor Cooper-White’s team at UQ first demonstrated the importance of viscoelasticity on stem cell behaviours in 2011, researchers around the world have been working to confirm those findings and probe other related mechanical properties of cells, building an in-depth body of knowledge that can be used to inform biological, medical and engineering research.

“The better we understand how cells behave in response to changes in the environment around them, the better we can understand how tissues and organs heal themselves, or how deadly diseases progress,” Professor Cooper-White said.

“This can potentially help us to find alternate treatment options targeted at re-establishing that extracellular environment back to ‘normal’ ­— these alternative treatments could certainly reduce suffering and save lives.

“The research has indicated that we are best to focus on creating biomaterials (materials that interact with biology) to better mimic our extracellular matrix viscoelastic properties in order to firstly understand how this universal mechanical property characteristic changes cells.

“We can then work on using that characteristic to our benefit when expanding stem cells for cell therapy, when growing tissues in the laboratory for eventual implantation, and even when developing injectable treatments to change diseased, stiff tissues back to healthy, soft and squidgy tissues.”

This is the first time that the world’s leading research groups have come together to highlight the importance of viscoelasticity in tissue development, repair and disease, and to discuss the potential for the development of new biomaterials for tissue engineering and regenerative medicine.

“Together, we hope that this review will drive our community to discover new methods to control cell behaviours so we can improve tissue healing and regeneration in the future, with better, more ‘tissue-like’ biomaterials.”

View this research review paper on Nature.