Scientists have for the first time grown a complex, fully functional organ from scratch in a living animal by transplanting cells that were originally created in a laboratory.
British scientists produced a working thymus, a vital immune system "nerve centre" located near the heart.
In future the technique, so far only tested on mice, could be used to provide replacement organs for people with weakened immune systems, scientists believe.
But it might be another 10 years before such a treatment is shown to be effective and safe enough for human patients.
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Rescue workers are at the site Sunday morning trying to cut open mangled coaches.
Despite chilly temperatures it will be a mostly dry day, and milder than yesterday.
The Sunday Times alleges a missile malfunctioned after launch during a routine test of the UK's nuclear deterrent last year.