Charla Nash who underwent a pioneering face transplant after being mauled by a chimpanzee has been taken back into hospital after her immune system began rejecting the tissue.
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She had been taking part in a military-funded experiment in which doctors at Boston's Brigham and Women's Hospital tried to wean her off the anti-rejection drugs she had been taking since the 2011 operation.
Nash tells The Associated Press she would appreciate any prayers and is confident her participation in the experiment will provide information to help treat disfigured soldiers returning from war.
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