Living organ regenerated for first time

A team of scientists at the University of Edinburgh has succeeded in regenerating a living organ for the first time. The team rebuilt the thymus, an organ in the body located next to the heart that produces important immune cells.The advance could pave the way for new therapies for people with damaged immune systems and genetic conditions that affect thymus development.

The team reactivated a natural mechanism that shuts down with age to rejuvenate the thymus in very old mice. After treatment, the regenerated organ had a similar structure to that found in a young mouse and the function of the thymus was also restored However, it is not yet clear whether the immune system of the mice was improved.

The study was led by researchers from the Medical Research Council Centre for Regenerative Medicine at the University of Edinburgh. The researchers targeted a protein produced by cells of the thymus - called FOXN1 - which helps to control how important genes are switched on. By increasing levels of FOXN1, the team instructed stem cell-like cells to rebuild the organ.

Professor Clare Blackburn from the MRC Centre for Regenerative Medicinesaid: “Ourresults suggest that targeting the same pathway in humans may improve thymus function and therefore boost immunity in elderly patients, or those with a suppressed immune system. However, before we test this in humans we need to carry out more work to make sure the process can be tightly controlled.”

The thymus deteriorates with age, which is why older people are often more susceptible to infections such as flu. The discovery could also offer hope to patients with DiGeorge syndrome, a genetic condition that causes the thymus to not develop properly.

Dr Rob Buckle, Head of Regenerative Medicine at the Medical Research Council said: “One of the key goals in regenerative medicine is harnessing the body’s own repair mechanisms and manipulating these in a controlled way to treat disease. This interesting study suggests that organ regeneration in a mammal can be directed by manipulation of a single protein, which is likely to have broad implications for other areas of regenerative biology.”

The study is published in the journal Development.

The basic unit of all living organisms. Full medical glossary
A viral infection affecting the respiratory system. Full medical glossary
The basic unit of genetic material carried on chromosomes. Full medical glossary
Relating to the genes, the basic units of genetic material. Full medical glossary
The organs specialised to fight infection. Full medical glossary
Invasion by organisms that may be harmful, for example bacteria or parasites. Full medical glossary
Compounds that form the structure of muscles and other tissues in the body, as well as comprising enzymes and hormones. Full medical glossary