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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Gunshots and explosions have been reported at Istanbul's Ataturk Airport.
Police say they are keeping an open mind about the motive and appealed for anyone with information to come forward.
Rain will clear east through this evening to leave a drier night for most, however showers will continue across some northern areas.