For the first time, researchers have used human embryonic stem cells to create new insulating tissue for nerve fibers in a live animal model – a finding that has potentially important implications for treatment of spinal cord injury and multiple sclerosis.
Researchers at the UC Irvine Reeve-Irvine Research Center used human embryonic stem cells to create cells called oligodendrocytes, which are the building blocks of the myelin tissue that wraps around and insulates nerve fibers. This tissue is critical for maintenance of proper nerve signaling in the central nervous system, and, when it is stripped away through injury or disease, sensory and motor deficiencies and, in some cases, paralysis result.
In this study, neurologist Hans Keirstead and colleagues at UCI and the Geron Corporation devised a novel technique that allows human embryonic stem cells to differentiate into high-purity, early-stage oligodendrocyte cells. The researchers then injected these cells into the spinal cords of mice genetically engineered to have no myelin tissue.
After transplantation into mice, the early-stage cells formed into full-grown oligodendrocyte cells and migrated to appropriate neuronal sites within the spinal cord. More importantly, the researchers discovered the oligodendrocyte cells forming patches of myelin’s basic protein, and they observed compact myelin tissue wrapping around neurons in the spinal cord. These studies demonstrated that the oligodendrocytes derived from human embryonic stem cells can function in a living system.
Results of this study are published online in the peer-reviewed journal Glia.
“These results are extremely exciting and show great promise,” Keirstead said. “What we plan to do next is see how these cells improve sensory and motor function, and hopefully it will lead to further tests with people who suffer from these debilitating illnesses and injuries.”
Gabriel I. Nistor and Minodora O. Totoiu from UCI collaborated with Nadia Haque and Melissa K. Carpenter of the Geron Corporation on the study, which was supported by Geron, UC Discovery, Research for Cure and the Reeve-Irvine Research Center. Geron provided the human embryonic stem cells used in this study.
In previous studies, Keirstead and colleagues have identified how the body’s immune system attacks and destroys myelin tissue during spinal cord injury or disease states. They’ve also shown that, when treated with antibodies to block immune system response, myelin is capable of regenerating, which ultimately restores sensory and motor activity.
The Reeve-Irvine Research Center was established to study how injuries and diseases traumatize the spinal cord and result in paralysis or other loss of neurologic function, with the goal of finding cures. It also facilitates the coordination and cooperation of scientists around the world seeking cures for paraplegia, quadriplegia and other diseases impacting neurological function. Named in honor of Christopher Reeve, the center is part of the UCI College of Medicine.