Stem Cells to Treat Blindness

    As if it were ripped from the pages of a science-fiction novel, scientists have been able to produce multiple types of eye tissue starting with just a pure culture of human stem cells. More amazingly, the researchers described transplantation procedures of the newly derived tissues that were able to repair damage to the front of the eye and restore vision in animal models of corneal blindness.

    The sight of blind rabbits were restored after researchers from Osaka University and Cardiff University used stem cells from humans to create living tissue that could repair eye ailments such as damaged lenses, retina and corneas. A separate study by American and Chinese scientists also used stem cell to regenerate new lenses for 12 human babies who had cataracts and had their lenses removed surgically.

    The eye is composed of highly specialized tissues that are derived from a variety of cell lineages during development. While previous studies demonstrated that particular cell types, such as those that constitute the retina or cornea, can be created in the laboratory from pluripotent stem cells, these studies do not, however, represent the complexity of whole eye development.

    “This research shows that various types of human stem cells are able to take on the characteristics of the cornea, lens and retina,” explained study co-author Andrew Quantock, Ph.D., professor and director of researcher at Cardiff University’s School of Optometry and Vision Sciences. “Importantly, it demonstrates that one cell type—the corneal epithelium—could be further grown in the lab and then transplanted onto a rabbit’s eye where it was functional, achieving recovered vision.

    In this new study the researchers report the generation of multiple cell lineages of the eye, including the lens, cornea, and conjunctiva, using human induced pluripotent stem cells. Moreover, they have been able to show that the corneal epithelial cells can be cultivated and transplanted onto the eyes of rabbits with experimentally induced blindness to repair the front of the eye surgically.

    The findings from this study were published today in Nature in an article entitled “Co-Ordinated Ocular Development from Human iPS Cells and Recovery of Corneal Function.”

    “Here we demonstrate the generation from human induced pluripotent stem cells of a self-formed ectodermal autonomous multi-zone (SEAM) of ocular cells,” the authors wrote. “In some respects the concentric SEAM mimics whole-eye development because cell location within different zones is indicative of lineage, spanning the ocular surface ectoderm, lens, neuro-retina, and retinal pigment epithelium. It thus represents a promising resource for new and ongoing studies of ocular morphogenesis.”

    The investigators were excited by their findings and are looking forward to taking the next steps toward clinical interventions.

“Our work not only holds potential for developing cells for treatment of other areas of the eye but could set the stage for future human clinical trials of anterior eye transplantation to restore visual function,” Dr. Quantock concluded.