Writing in the journal Science, Professor Derby of The School of Materials, looks at how the concept of using printer technology to build structures in which to grow cells, is helping to regenerate tissue.
Both inkjet and laser printer technology can be used to build the 3D scaffolds that cells can be grown in and also place the cells in these structures simultaneously. Professor Derby explains how bioprinting works: "Inkjet technology places the structure's material in small droplets, which then solidify. More droplets are then placed on top of the previous ones in a specific pattern. The structure is built using this method which is generally referred to as additive manufacture.
"Laser printing uses light to solidify the structure's material layer upon layer. These methods have allowed us to develop very complex scaffolds which better mimic the conditions inside the body."
The scaffold provides a surface for the cells to adhere, thrive and multiply. Both the scaffold material, composition and its internal architecture control the behaviour and well-being of the cells inside.
In his review article Professor Derby looks at experiments where porous structures have been made through bioprinting. They are then placed in the body to help act as a scaffold to encourage cell growth. The cells colonize the structure and it either dissolves or becomes part of the body.
This type of treatment can help patients suffering from problems such as cavity wounds. Clinical trials are currently taking place around the world to perfect this technology, and Professor Derby says it is moving towards becoming an established form of science.
Professor Derby also looks at how stem cells are being grown in printed structures that have been impregnated with certain chemicals. The chemicals are inserted during the printing process and can determine the type of cell the stem cells develop into. For example stem cells could be programmed to become cells that make up bone tissue or cartilage.
But there are limitations to the technology which is holding back breakthroughs such as the ability to grow an entire organ. Studies have found that it is very difficult to actually print the cells at the same time as making the structure that will house them. The stress on the cell as it goes through both the inkjet and laser process can damage the cell membrane. Cell survival rates have also been variable, ranging from between 40 to 95%.
The technology is also some way off progressing from an experimental platform to clinical practice. Whilst scaffolds are being clinically trialled, actually transplanting cells grown in an external structure into a patient is a more advanced process. It is still not possible at present to guarantee a consistent quality, which is required by medical device regulations.
But research is being carried out to grow external cells into tissue, such as a patch of skin, and transplant that into a patient. Professor Derby is currently working with Ear, Nose and Throat surgeons at the Manchester Royal Infirmary. He wants to use bioprinting to print cells without using a scaffold. The printed cells form a sheet that can be used for grafts inside the body, for example in the mouth or nose.
Professor Derby says: "It is very difficult to transplant even a small patch of tissue to repair the inside of the nose or mouth. Current practice, to transplant the patient's skin to these areas, is regarded as unsatisfactory because the transplants do not possess mucous generating cells or salivary glands. We are working on techniques to print sheets of cells that are suitable for implantation in the mouth and nose."
One area which Professor Derby's review article highlights for the future is the ability to grow structures which can model cancerous tumours. These could then be used to test new drugs, which it's hoped will advance the search for more effective treatments.
Writing the review article has encouraged Professor Derby that there is a strong future for bioprinting and whilst growing organs is still a long way off, the advances being made in this area are very promising.
University of Manchester: http://www.manchester.ac.uk
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Structural colours are more visible and vivid than those that use pigments as many examples from the natural world demonstrate. But sometimes pure white is what is required
Dutch biologist Ingrid van der Meer often meets with disbelief when she talks about her work on dandelions and how it could secure the future of road transport.
Pretend for a minute that it’s 1875 and you’re a mining engineer whose job it is to figure out how much gold is in them thar hills. Get it wrong, and your company is going to waste a lot of time and money hunting for gold that’s not there—or worse yet, miss out on the mother lode
It can only switch from black to transparent and back again, but that's a start
What happens when you add folds to materials that are only a few atoms thick? Several scientists set out to find the answer — and discovered that these nano-wrinkles can be quite useful.
A battery tattoo powered by perspiration has been unveiled by chemists in California.
Huge earthquakes could be on the way to Chile, after the major quake in April this year failed to relieve seismic stresses that have built up for 150 years
The Swedish government is looking at building a nuclear reactor purely for research, although a decision will not be taken until after a general election in September, Swedish daily Dagens Industri reported.
A new movie turns the physicist into a romantic lead. But how will it handle the not-so-wonderful parts of his marriage? Truthaholics want to know.
Iranian mathematician Prof Maryam Mirzakhani becomes the first woman to win a Fields Medal at a ceremony in Seoul, South Korea.