Human neural stem cells protect cone photoreceptors: StemCells preclinical data

Oct 20 2009

StemCells, Inc. (NASDAQ:STEM) announced today new preclinical data showing that its human neural stem cells protect cone photoreceptors (cones) in the eye from progressive degeneration and preserve visual function long term. Cones are light sensing cells that are highly concentrated within the macula of the human eye, and the ability to protect these cells suggests a promising approach to treating age-related macular degeneration (AMD), the leading cause of vision loss and blindness in people over the age of 55. These important findings were presented today in Chicago, Illinois at the Society for Neuroscience 2009 Annual Meeting, one of the leading forums for neuroscientists from around the world to present and discuss cutting-edge research in the field.

“We have long recognized that a number of eye disorders may be suitable candidates for stem cell-based therapies,” stated Stephen Huhn, MD, FACS, FAAP, vice president and head of the CNS program at StemCells, Inc. “The demonstrated ability of our human neural stem cells to preserve cones is very meaningful, because it is the progressive deterioration of these specific cells that ultimately results in vision loss in AMD. These data support our hypothesis that our neural stem cells may provide neuroprotection to existing cells, and it is our hope that we will be able to replicate these promising results in the clinic.”

This study, which was conducted in collaboration with researchers from the Casey Eye Institute at Oregon Health & Science University (OHSU), focused on assessing photoreceptor survival and vision preservation following transplantation of StemCells’ human neural stem cells. Results of the study demonstrate that, when transplanted into the eye of the Royal College of Surgeons (RCS) rat, a well-established animal model of retinal degeneration, the neural stem cells preserve visual function as measured by two separate visual tests, and exhibit robust, long-term protection of both rod and cone photoreceptors.

Raymond Lund, Ph.D., professor of Ophthalmology at the Casey Eye Institute, commented, “My lab has been involved in researching many cell therapy approaches for diseases of the eye, and the results we have seen with the human neural stem cell are particularly exciting. This study provides novel evidence that neural stem cells may provide significant therapeutic value for clinical cases of retinal degeneration, and we look forward to testing their potential in additional studies with StemCells, Inc.”

The eye contains millions of photoreceptor cells, known as rods and cones, which are responsible for picking up light and converting it into electrical impulses that are sent along the optic nerve for the brain to interpret what we see. Rods allow us to see under dark conditions, while cones allow us to see color and fine detail. Cones are highly concentrated within the macula, the part of the eye that is responsible for our central, “straight ahead” vision. Patients with AMD lose central vision when the cones within the macula degenerate. It is estimated that 25 – 30 million people worldwide suffer from AMD, including as many as 15 million Americans, and today there is no cure.

StemCells is pursuing additional preclinical studies of its neural stem cells in the hope of one day achieving a breakthrough in treating AMD. The encouraging results of this latest study follow previously reported data showing that StemCells’ neural stem cells engraft, survive long term, and can protect the retina from progressive degeneration in the RCS rat. StemCells is currently developing its human neural stem cells as a potential therapeutic product, HuCNS-SC^® cells, for multiple degenerative disorders of the central nervous system.