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Japanese team conducts world’s first eye transplant using donor iPS cells

JIJI, Kyodo

A team led by the government-affiliated research institute Riken said Tuesday that it had carried out the world’s first surgery transplanting retina cells created from donor iPS cells.

By using a stockpile of induced pluripotent stem cells at Kyoto University, not iPS cells made from the patient’s own mature cells, the team reduced the time and costs necessary for the procedure.

The surgery opens a new phase for Japan’s regenerative medicine utilizing iPS cells.

The patient in his 60s, who lives in Hyogo Prefecture, had been suffering from exudative age-related macular degeneration, an intractable disease that could lead to blindness.

During the one-hour operation on Tuesday afternoon, 50 microliters of liquid containing 250,000 retinal pigment epithelial cells was injected into the retina of the patient’s right eye.

The surgery was conducted at Kobe City Medical Center General Hospital by Yasuo Kurimoto, head of the hospital’s department of ophthalmology, and others. Kurimoto told a news conference that the surgery was completed without complications.

The head of the team, Riken researcher Masayo Takahashi, said it will take a few years to determine if the operation was a success. Following an observation period of one year, the patient will receive follow-up checks for three years.

“A key challenge in this case is to control rejection,” said Takahashi, 55. “We need to carefully continue treatment.”

The surgery used iPS cells from people who have immunological types with a lower risk of rejection. The Riken Center for Developmental Biology (CDB) transformed the iPS cells into retinal pigment epithelial cells.

In a similar operation on a woman with the same disease in September 2014, the CDB-led team succeeded in the first transplant of retina cells made from iPS cells, but those were from the same patient.

That case took 10 months before the patient received the transplant and cost nearly ¥100 million ($900,000).

Following the operation, the team decided it was better to use retinal cells derived from donated iPS cells.

Upon receiving health ministry approval in February this year, the team picked five candidates between ages 50 and 85 from applicants with macular degeneration.

By using stockpiled iPS cells, the time until surgery can be shortened to a month and costs cut to under ¥20 million.

A similar surgery is also planned to take place at Osaka University Hospital.