Positive results from Japan's pioneering stem cell transplant trial

The first trials to test whether reprogrammed stem cells can repair diseased organs have begun to report positive results

In January, researchers reported in a preprint that Japan's first transplant of cardiomyocytes made from reprogrammed stem cells had improved heart function after surgery

The ongoing trials "provide encouraging first-hand insights into the evolution of iPS cell therapy, from the laboratory to the patient," says pharmacologist Wolfram-Hubertus Zimmermann of the German University Medical Center (Göttingen)

By far the biggest impact of the mutagenic stem cell trials in Japan is that they "give people the world the confidence that this is possible," says Kapil, a translational stem cell researcher at the National Eye Institute in Bethesda, Maryland.

The field of iPS cells is hugely popular in Japan, in large part because a local Japanese scientist, Shinya Yamanaka of Kyoto University, discovered how to make cells

During this period, Japanese scientists have conducted at least 10 human trials

iPS cell technology is only 16 years old

treat vision loss

This corneal study aims to treat people with severe vision impairment due to a lack of stem cells needed to repair the cornea

Nishida's trial isn't the first time induced pluripotent stem cells have been used to repair eye disease

In a press release on April 4, Nishida reported the first evidence that iPS cell therapy improves vision

encouraging results

Researchers outside Japan said the corneal trial was too small to determine the effectiveness of the treatment, but they were encouraged by the results

In Japan, the observed beneficial effects of such cells have boosted the morale of scientists

There are also encouraging signs from another ongoing trial in which donor cells are reprogrammed into cardiomyocytes, said Yoshiki Sawa, a cardiac surgeon at Osaka University who led the trial

To gain industry support, scientists need to show that these treatments work, says neurosurgeon Jun Takahashi of Kyoto University

He is involved in a trial that uses donor-derived iPS cells to generate dopamine-producing neurons, the results of which are expected soon
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They implanted these cells into the brains of seven Parkinson's patients between 2018 and 2021
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No serious adverse events have been observed so far, Takahashi said
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Participants will be observed for two years after surgery and assessed for neurological symptoms, with results expected in 2024
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"The best case scenario is that the patient's symptoms improve," he said
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If trials show strong clinical efficacy and no side effects, the treatments could become the first to receive conditional approval for sale in Japan as part of the government's fast-track program for regenerative medicines
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