New method for mass-producing RPE cells paves way to treating age-related blindness

Durham, NC – Scientists have developed a new, simpler way to produce human pluripotent stem cells in quantities large enough that they can be used to develop treatments for age-related macular degeneration — the leading cause of irreversible blindness among the elderly. The results of this new study are published in the current issue of STEM CELLS Translational Medicine.

Age-related macular degeneration (AMD), which affects up to 50 million people worldwide, is associated with the dysfunction and death of retinal pigment epithelial (RPE) cells.

“As a result, there has been significant interest in developing RPE culture systems both to study AMD disease mechanisms and to provide substrate for possible cell-based therapies. Because of their indefinite self-renewal, human pluripotent stem cells (hPSCs) have the potential to provide an unlimited supply of RPE-like cells,” noted Donald Zack, M.D., Ph.D., who with Julien Maruotti, Ph.D., led the team of researchers from the Wilmer Institute, Johns Hopkins University School of Medicine in Baltimore, Md., and the Institute of Vision in Paris in conducting the study.

“However, most of the currently accepted methods in use for deriving RPE cells from hPSC involve time-and-labor-consuming  steps done by hand, and they don’t yield large enough amount of the differentiated cells – which has posed a problem when trying to use them to develop potential new therapies,” Dr. Maruotti added.

The Zack/Maruotti team simplified RPE cell production by modifying a standard protocol for isolating the cells from spontaneously differentiating hPSC monolayers. In the new method, hPSCs were amplified by clonal propagation and the RPE cells enriched by serial passage rather than mechanical picking.

“These modifications eliminate the need for the time- and labor consuming manual steps usually required to culture hPSCs and to purify the RPE population, and thereby provide a readily scalable approach to generate large numbers of high quality RPE cells — up to 36 times more than the best protocols previously reported during the same time interval,” Dr. Zack said.

“This improved process represents a step toward mass production of RPE and could prove useful for applications requiring large number of cells such as cell therapy, drug screening or disease modelling,” said Anthony Atala, M.D., Editor of STEM CELLS Translational Medicine and director of the Wake Forest Institute for Regenerative Medicine.