By MASATOSHI TODA/ Staff Writer
A Keio University research team has been given the green light to transplant heart muscle cells derived from iPS cells into patients who have experienced severe heart failure.
The university on Feb. 6 announced that its internal committee had issued its consent for the team to carry out a clinical study of the transplants.
The team, led by Keiichi Fukuda, a professor of cardiovascular internal medicine at the university, aims to conduct the study by the end of fiscal 2020.
The study targets patients with dilated cardiomyopathy, which lowers the systolic function of heart muscle cells.
Once heart muscle cells have begun to decline, they are unable to regain their full ability to function. If already damaged heart muscle cells continue to deteriorate, patients often require heart transplants or ventricular assistance devices.
But due to a shortage of donors, only 50 or so transplants are conducted annually, leading to a growing need for new forms of treatment.
Fukuda's team has been studying a treatment using iPS cells, which can grow into any type of tissues.
The team will turn iPS cells provided by Kyoto University into heart muscle cells and create cardiomyocyte balls for transplants. Each cardiomyocyte ball contains 1,000 iPS-derived heart muscle cells.
Since the heart is covered by a layer of fat that is a few millimeters thick, the heart muscle cells need to be transplanted below the layer to make the heart beat.
To avoid damaging the heart, a special needle will be used to inject cardiomyocyte balls into small holes made on the surface of the heart.
The team will start its trial by transplanting 50 million heart muscle cells per patient, the minimum amount that the team has confirmed is safe.
The more iPS-derived cells a patient receives, the higher their risk that the cells may become cancerous.
Three patients will receive transplants. The team will then spend a year monitoring the effects, including whether the recipients experience severe irregular heartbeats and whether the transplanted cells develop tumors.
A team of doctors at Osaka University is also working to develop regenerative heart medicine using iPS cells. The team has already started a clinical trial to treat ischemic cardiomyopathy, or clogged blood vessels, and transplanted sheets of heart muscle cells into one patient last month.