Researchers from Johns Hopkins University have developed a method to efficiently turn human stem cells into retinal nerve cells that transmit visual signals from the eye to the brain.
Death and dysfunction of these cells cause vision loss in conditions like glaucoma and multiple sclerosis (MS).
"Our work could lead not only to a better understanding of the biology of the optic nerve, but also to a cell-based human model that could be used to discover drugs that stop or treat blinding conditions," said study leader Donald Zack from Johns Hopkins' School of Medicine.
Eventually, it could lead to the development of cell transplant therapies that restore vision in patients with glaucoma and MS.
Using a genome editing laboratory tool, investigators inserted a fluorescent protein gene into the stem cells' DNA.
They used a technique called fluorescence-activated cell sorting to separate out the newly differentiated retinal ganglion (nerve) cells from a mixture of different cells into a highly purified cell population for study.
"The cells showed biological and physical properties seen in retinal ganglion cells produced naturally," Zack noted.
Researchers also found that adding a naturally occurring plant chemical called forskolin on the first day of the process helped improve the cells' efficiency of becoming retinal ganglion cells.
The researchers, however, caution that forskolin which is used for weight loss and muscle building, is not scientifically proven safe or effective for treatment or prevention of blindness or any other disorder.
"By the 30th day of culture, there were obvious clumps of fluorescent cells visible under the microscope," noted lead author Valentin Sluch, now a postdoctoral scholar working at Novartis, a pharmaceutical company.
In follow-up studies, the team is looking to find other genes that are important for ganglion cell survival and function.
"We hope that these cells can eventually lead to new treatments for glaucoma and other forms of optic nerve disease," the authors noted in a paper appeared in the journal Scientific Reports.