A Japanese research team on Friday transplanted a retina sheet made of induced pluripotent stem cells into a human body for the first time in the world, the team said.
The researchers, from the scandal-hit Riken institute, said the operation involved an attempt to regenerate retina cells in a female patient in her 70s with age-related macular degeneration.
The procedure took place at the Institute of Biomedical Research and Innovation Hospital in Kobe. The surgeons included the hospital’s own Yasuo Kurimoto.
The transplant comes after Kyoto University professor Shinya Yamanaka developed iPS cells that can grow into any type of human tissue. The research won Yamanaka the 2012 Nobel Prize in physiology or medicine, which he shared with fellow researcher John Gurdon, because it has applications in regenerative medicine and drug development.
The transplant was conducted by a team led by ophthalmologist Masayo Takahashi of the Riken Center for Developmental Biology, as part of a clinical study. Takahashi’s team developed techniques to treat age-related macular degeneration in the exudative form, a condition that can cause sudden loss of vision due to retinal damage.
The team extracted skin cells from the patient and created iPS cells from them, which were later developed into a layer of cells known as pigment epithelium. These were transplanted into the patient.
During the roughly two-hour surgery, the retinal sheet was transplanted onto the patient’s eye after removing abnormal vessels in her retinal tissue, according to Riken.
Afterward, nothing serious or harmful happened to the patient and there was no undue blood loss. The patient is expected to be released in three to seven days, the team said.
Riken sought government permission to conduct clinical research on regenerating retinas via iPS cells in February last year. Approval was granted in July.
Through the research, the team will check whether iPS cell transplants can cause problems in patients, including cancer. Since the clinical research would cover patients on whom existing medicine does not work, as well as those have nearly lost their sight due to the disease, the transplants will not dramatically improve their eyesight, Riken officials said.
The next stage of clinical research would be full-fledged tests conducted on patients in the early stages of the disease, with a view to restoring their eyesight, the researchers said.
Riken hopes to commercialize the iPS cell transplant procedure by around 2020.
The study was overshadowed by a STAP cell research fraud earlier this year involving biologist Haruko Obokata, also a member of the Riken center. Takahashi criticized Riken’s handling of the incident and said in a message on Twitter in July that she may have to consider suspending her study.