UK researchers have restored an elderly organ in mice which has opened the path for the procedure to be used on humans.
The thymus is vital for immune function, but it shrinks and loses its effectiveness with age, causing people to become more prone to infection.
A team of researchers at the University of Edinburgh have managed to rejuvenate this organ in mice by the manipulation of DNA.
The thymus, situated close to the heart, is responsible for the production of T-cells which fight infection. By the time the age of 70 is reached, the thymus has reduced to one tenth of the size it was during adolescence.
One of the team of researchers, Dr Nick Bredenkamp, has stated that this reduction impacts on older individuals because their immune system has decreased with age and they have become more at risk of infection and less responsive to available vaccines.
The team made use of old mice to try and regenerate the thymus. As the thymus starts to age, the gene Foxn1 starts shutting down naturally. The researchers tried to boost it back to the levels it was at during youth by using a drug to increase the genes activity.
The results, which have been published in ‘Development’, indicated that a boost of the gene activity in the elderly mice provided them with the thymus of an animal of a much younger age.
Dr Bredenkamp stated that it was possible for them to use this method for regeneration as it increases the size and development of additional T-cells. He said that it had almost regenerated completely.
He stated that their excitement was increased because of the way in which the tests were done. The team targeted one gene and have been able to regenerate a complete organ.
Scientists are not sure why the thymus becomes smaller with age. The one theory they offer is that it requires a lot of energy to operate and the body diverts this towards reproduction once it reaches adolescence.
Dr Bredenkamp said that this method could ultimately be adapted for use in humans, but the process would have to be ‘very tightly controlled’ in a bid to ensure that the body’s immune system does not overreact and start attacking the body.
This study has raised prospects of other body organs, such as the heart or brain, being used to become more youthful by targeting one gene.
The Head of Regenerative Medicine at the Medical Research Council, Dr Rob Buckle, has said that one of the main goals of regenerative medicine is to harness the repairs mechanisms of the body and manipulating it in a controlled fashion to treat disease.
He said that this study has shown that organ regeneration in mammals can be done by manipulating one protein and that it could have much wider implications in other areas of regenerative biology.
Image credit: Understanding Animal Research