Japanese researchers say they have transplanted cornea tissue developed from artificially derived stem cells in the world's first clinical trial of its kind.
A group of researchers led by Osaka University Professor Koji Nishida spoke to reporters on Thursday.
The researchers said they performed the transplant on July 25 on the left eye of a female patient in her 40s. She had a serious cornea disease.
They said they used sheet-like corneal tissues produced from human iPS cells, or induced pluripotent stem cells.
The doctors said that the patient has not yet shown a rejection response and her vision has recovered so she no longer has trouble in her daily life.
They said that the woman left hospital last Friday.
The team plans to perform the same transplant on a second patient by the end of the year and perform two more transplants next year.
The study is the latest in a series of clinical tests using iPS cells, including a transplant of retina cells into a patient with a different eye disease.
Professor Nishida said that the female patient who had almost no vision has regained the ability to read letters.
He also said a lot of things about treatment of cornea diseases still remain unknown and his team wants to carefully check safety and effectiveness.