Using milk protein to 3D-imprint muscle and bone cells
Wednesday, 19 July 2017
A University of Canterbury PhD student is using milk protein to 3D-imprint muscle and bone cells and one day she hopes her research may be used to regrow missing body parts.
Electrical and Computer Engineering doctoral candidate Azadeh Hashemi, originally from Tehran, Iran, came to start her PhD at the University of Canterbury (UC) four years ago.
Azadeh’s successful work in UC’s Biomolecular Interaction Centre is turning what is basically milk powder into biomedical devices, such as implants to help regrow missing body parts. Her work is focused on fabrication of casein-based films with surface patterns, and growing cells on them.
“The aim of my work is to replicate a 3D imprint of cells onto films made of milk protein, to use them as a substrate for growing cells. Development of the replication process and controlling the biodegradability of these films are the main parts of this work,” she says.
“The patterns on these biodegradable cell culture substrates mimic the cells’ natural physical environment and they can influence cell shape and growth. Once they have done their job, the films gradually degrade and leave the grown tissue behind.”
The possibilities of these micro- and nanostructures are tantalising, with applications in stem cell engineering, regenerative medicine, and implantable devices.
“If they can help the cells grow into muscles, bones or other tissues they would be able to replace any missing body part and help them regrow,” Azadeh says.
“Another great application for these substrates is to grow stem cells on an imprint with patterns of different cell types and see what type of cell the stem cells would change into. We might even be able to stop cancer cells from being cancerous by growing them on these patterns, in which case the biodegradability of the substrates would also be an advantage for eliminating the need for secondary surgery.”
These materials have not been used in the human body yet, but in theory their application could help recovery from injury or disease with muscle or bone replacement.
“These films could especially be used as implants to help missing tissue or muscle regrow using the surface patterns as a guide. The biodegradable implant would then just dissolve and there won’t be any need for secondary surgery to take the implant out.”
The project is based on a collaboration between Dr Volker Nock of UC’s Biomolecular Interaction Centre and Dr Azam Ali, formerly AgResearch, now at the University of Otago. It was initiated through the Biomolecular Interaction Centre via a summer scholarship.
The early results were promising and Azadeh's work took it to the next level, Dr Nock, her PhD supervisor, says.
“Azadeh's work has demonstrated that we can replicate the shapes of biological cells into casein biopolymers with extremely high-resolution, that we can control how long these materials take to degrade and that we can culture other cells on top of them. She is just now getting her first results as to what influence the shapes have on the cells and how the shapes change over time. One premise is that plastic (bio or not) with the shape of similar cells imprinted on the surface may positively influence the response of other real cells encountering such a surface,” he says.
Azadeh’s research also builds on the work of her PhD co-supervisor UC Professor Maan Alkaisi and his students in developing a method of imprinting the shapes of cells into plastic.
“We now have a biodegradable, pattern-able surface on which we can culture cells. The patterns can for example be used to help guide cells during muscle fibre formation in a Petri dish, while slowly being dissolved by the cells in the process so that only the finished tissue remains,” Dr Nock says.
Azadeh recently returned to Christchurch from the United States where she was invited to give a presentation at one of the largest micro- and nanofabrication conferences in the world, the International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication, based on a prize she won last year at a European conference in Vienna, Austria (International Conference on Micro & Nano Engineering). She co-wrote the academic paper Fabrication of free-standing casein devices with micro- and nanostructured regular and bioimprinted surface features.