Scientists regenerate immune organ in mice

By Kate Kelland LONDON (Reuters) – British scientists have for the first time used regenerative medicine to fully restore an organ in a living animal, a discovery they say may pave the way for similar techniques to be used in humans in future. The University of Edinburgh team rebuilt the thymus – an organ central to the immune system and found in front of the heart – of very old mice by reactivating a natural mechanism that gets shut down with age. The regenerated thymus was not only similar in structure and genetic detail to one in a young mouse, the scientists said, but was also able to function again, with the treated mice beginning to make more T-cells – a type of white blood cell key to fighting infections. The regenerated thymus was also more than twice the size of the aged organs in the untreated mice.