To help repair muscles and ligaments, scientists are developing a flexible scaffolding made of soluble glass along which implanted healthy cells can grow. Other potential applications of the technique include treatment of gum disease and muscular dystrophy.
When the soft tissues of our bodies, for example muscle and ligaments, are damaged by disease or accident, one possible treatment is to insert healthy cells which can grow and repopulate the injured area. However, delivering cells to the damaged region and ensuring that they remain in place and grow in the correct way is a problem. Now Professor Irwin Olsen and his colleagues Drs. Jonathan Knowles and Mark Lewis at the Eastman Dental Institute (University College London) are developing new materials called soluble glasses that could provide a novel way to ‘seed’ injured tissues with healthy cells and also to act as a temporary, flexible scaffold enabling the growing cells to adopt the appropriate architecture.
Successful Repair of Damaged Tissues
“One major factor in successfully repairing damaged tissue is putting the new healthy cells in the right place and encouraging them to grow in the right way”, says Professor Olsen. “With hard tissues such as bone you can use stiff, permanent structures such as titanium as a scaffold, but with softer tissues you need a material that is more flexible and preferably only temporary, so that it will dissolve over time as it is replaced by the growing new cells”.
Novel Soluble Glass-Based Materials
The novel glass-based materials developed at the Eastman are based on phosphate, rather than silica as in conventional glass, and can be made into very fine, flexible fibres that are also ‘soluble’. In addition, the surface chemistry of these fibres would allow a variety of substances to be attached, including molecules that might promote the growth of new cells and even genes that could correct a defective cell.
Treatment of Periodontal Disease
One area of interest to the Eastman tissue engineering team is periodontal disease, where the ligaments that anchor the tooth to the jaw break down. It might be possible to attach healthy ligament cells to the soluble glass fibres and surgically implant them in the damaged area. Over time the ligament would regenerate and the fibres would disappear.
Treatment of Muscular Dystrophy
The researchers are also interested in muscle damage and disease. Preliminary experiments have already shown that healthy muscle cells will attach and grow on these new glass structures in the test tube. It may therefore be possible to take normal muscle cells seeded onto the soluble glass fibres, implant them into the diseased muscle and allow them to develop into healthy muscle. The Eastman group is now working closely with Dr. Jennifer Morgan, senior scientist in the Muscle Cell Biology Group headed by Professor Terence Partridge at the MRC Clinical Sciences Centre (Imperial College School of Medicine) to see if this technique might eventually be useful in treating muscular dystrophy.