StemCells, Inc announced positive results of a preclinical study using the company's human neural stem cells (hCNS-SC) to regenerate myelin, a nerve fiber insulator that is often lost or damaged in spinal cord injury, multiple sclerosis and certain genetic disorders. Dr. Stan Tamaki, Ph.D., senior scientist at StemCells, Inc., will present these findings at the 33rd Annual Society for Neuroscience Meeting in New Orleans taking place November 8-12, 2003.

Results of the study show extensive myelination of nerve axons in a mouse that cannot produce myelin because it lacks a functional copy of the basic myelin protein gene. The mouse is known as the 'shiverer' mouse model because the absence of myelin in the nerves of the spinal cord produces shivering behavior. Dr. Tamaki will present evidence that the company's hCNS-SC, when transplanted into the shiverer mouse, generate human oligodendrocytes that functionally integrate into the brain and produce myelin, resulting in widespread insulation of the mouse nerve axons.

"Damage to myelin is the primary factor responsible for the extensive muscle and organ malfunction associated with conditions such as spinal cord injury and multiple sclerosis," said Dr. Tamaki. "By regenerating healthy myelin producing oligodendrocytes, we may potentially be able to alleviate these symptoms that so many patients suffer from."

Since destruction of myelin also occurs in spinal cord injury, the data obtained from the "shiverer" mouse study helps elucidate the mechanism of functional recovery seen in a previously reported preclinical spinal cord injury study sponsored by StemCells Inc. In a collaborative endeavor with Drs. Aileen J. Anderson and Brian J. Cummings of the Reeve-Irvine Center at the University of California, Irvine, StemCells Inc.'s hCNS-SC were evaluated in mice with spinal cord injuries. Transplanted injured mice showed improved motor function in comparison with controls. Moreover, the degree of functional recovery was directly linked to the level of human cell engraftment. The company's collaborators at the SFN meeting will present additional data from these studies.

The deficiency of functional myelin is also characteristic of many lysosomal storage disorders, such as Krabbe's, Metachromatic Leukodystrophy, and Tay-Sachs disease. The company has previously reported on the preclinical efficacy of its cells for treatment of Neuronal Ceroid Lipofuscinosis, a lysosomal storage disease commonly referred to as Batten's Disease. Transplantation of the company's hCNS-SC into the brains of Batten mice resulted in a significant reduction in the amount of stored waste material and protection of neuronal cells from further loss. An update of this study will be the subject of a presentation by the company's collaborators at the SFN meeting.

"StemCells has now established, in live animal models, that its human neural stem cell gives rise to the three major cell types of the central nervous system, i.e. neurons, astrocytes and oligodendrocytes. Above all, we have shown that these derivative cells function and behave accordingly. With these recent results, we believe we are definitively moving closer to being able to treat a wide array of diseases or injuries to the brain and spinal cord," said Martin McGlynn, president and CEO of StemCells.