Stem cell therapy looks promising against macular degeneration

Thursday, January 17, 2019 (HealthDay News) – Age-related macular degeneration is the leading cause of vision loss in the elderly, and existing treatments are rare.

But now, experiments on pigs and rats suggest that stem cell therapy could help stop at least one form of the disease.

The findings may soon lead to early human trials of this therapy for macular degeneration, according to researchers at the American American Eye Institute (NEI).

The rats and pigs participating in this study had geographic atrophy, the advanced "dry" form of the disease.

An ophthalmologist has been cautiously optimistic about the new report.

"This could lead to an improvement in the visual function of people with age-related macular degeneration of the dry form, for whom there is currently no curative treatment," said Dr. Mark Fromer, ophthalmologist at Lenox Hill Hospital in New York.

However, despite the early promise of these animal studies, "clinical trials on humans are needed to develop these revolutionary new techniques," said Fromer.

The new research was led by Kapil Bharti, who heads the translational research unit on NEI eye cells and stem cells. His team used human blood cells and converted them to the laboratory into so-called induced pluripotent cells (iPS cells). These are cells that can grow in any type of body cells.

In this case, iPS cells, or iPSCs, have been programmed to become retinal pigment epithelial cells (RPEs) – the type of cells that die at the early stage of AMD.

RPE cells are essential for vision as they feed the photoreceptors, light-sensing cells located in the retina of the eye.

According to NEI researchers, just 10 weeks after the implantation into the pig and rat retina of special "cells" of iPSC-derived human ESR cells, they had integrated with the retina and functioned properly.

One of the major concerns of any type of stem cell therapy is the risk that cells will multiply uncontrollably and form tumors. But a genetic badysis of the iPSC-derived RPE cells used in this study did not reveal any such mutations, said the Bharti team.

And since the patient's cells are used as a source of transplanted cells, this "minimizes the chances of [transplant] rejection, "Bharti explained in a press release from NEI.

Based on these promising results, planning for an early clinical trial to test the safety of stem cell therapy is ongoing. The trial would begin after approval by the US Food and Drug Administration, the researchers said.

Dr. Matthew Gorski is an ophthalmologist at Northwell Health in Great Neck, New York. He acknowledged that "the positive results of this study are an important step in the search for a cure for certain types of macular degeneration".

Nevertheless, experiments on animals do not always take place in humans. "So it will take many more years of experiments before knowing if this technology can be used successfully to treat macular degeneration," Gorski said.

The study was published Jan. 16 in the journal Translational medicine science.

More information

Find out more at the American Foundation for Macular Degeneration.