For the past 40 years scientists have been telling us that stem cells will revolutionise medicine, but we've yet to see that potential materialise. That may soon be about to change – after decades of groundwork Australian scientists at the University of New South Wales have developed a world-first technique that allows them to regrow muscle tissue in mice using adult stem cells.
The breakthrough could help sufferers of muscle wasting diseases such as muscular dystrophy. Normally incurable, muscular dystrophy affects around 21,000 Australians.
The implications of being able to regrow whole tissue groups are enormous. The way is now set for scientists to regenerate areas of the liver, pancreas, spine and brain, which means we could one day find a cure for Alzheimer’s, paralysis and diabetes. “What has been the realm of science fiction is looking more and more like the medicine of the future,” said Professor Peter Gunning, one of the lead researchers.
Scientists worldwide have been trying to grow muscles for years, but Gunning's team succeeded because it first ‘weeded out’ the old cells using chemotherapy. This gave the introduced stem cells the time they needed to establish themselves and regrow the muscle without competition.
The scientists are now looking to trial the treatment in humans. As they used adult muscle stem cells, which can be obtained from a willing donor, there are no legal or ethical complications. However, only a few types of adult stem cells have been discovered and properly characterised. In the future researchers may need to turn to embryonic stem cells to treat a broader range of diseases, which will raise ethical issues.
Embryonic stem cells are taken from human embryos, making their use controversial, but they have the potential to develop into any tissue type in the human body. This includes nerves, which could one day be used to help people paralysed by spinal injuries walk again.
The legal and ethical debate surrounding embryonic stem cells has constrained the scientific community's understanding of them, but this may soon no longer be the case now that US President Barack Obama has reversed the funding ban on embryonic stem cell research in the US. “New tools will be developed, new ideas will come out and, because it’s a global community, we’ll all be benefitting", says Gunning. He adds, "It’s clear that stem cell therapy is going to change medicine.” It may have been a long time coming, but stem cells are finally starting to measure up to their hype.
How it works
Scientists have failed to regrow muscle tissue in the past because the donor stem cells that they used were quickly out-competed by existing cells. This was overcome by making them resistant to chemotherapy and then using chemotherapy to wipe out the old tissue. The same process can be used to regenerate tissue in the brain, pancreas or liver. If scientists could learn to use embryonic rather than adult stem cells they could potentially regrow any tissue type in the body.