Source: Case Western Reserve University
Date: September 26, 2011
Summary:
Scientists at Case Western Reserve University School of Medicine found a way to rapidly produce pure populations of cells that grow into the protective myelin coating on nerves in mice. Their process opens a door to research and potential treatments for multiple sclerosis, cerebral palsy and other demyelinating diseases afflicting millions of people worldwide. The findings were published in the online issue of Nature Methods, Sunday, Sept. 25.
With this new discovery, scientists are now able to direct mouse stem cells into populations of myelinating cells, called oligodendrocyte progenitor cells, or OPCs. in just 10 days. The team’s success relied upon guiding the cells through specific stages that match those that occur during normal embryonic development.
First, stem cells in a petri dish are treated with molecules to direct them to become the most primitive cells in the nervous system. These cells then organize into structures called neural rosettes reminiscent of the developing brain and spinal cord. To produce OPCs, the neural rosettes are then treated with a defined set of signaling proteins previously known to be important for generation of OPCs in the developing spinal cord.
After this 10 day protocol, the researchers were able to maintain the OPCs in the lab for more than a month by growing them on a specific protein surface called laminin and adding growth factors associated with OPC development. The OPCs were nearly homogenous and could be multiplied to obtain more than a trillion cells. The OPCs were treated with thyroid hormone, which is key to regulating the transition of the OPCs to oligodendrocytes. The result was the OPCs stopped proliferating and turned into oligodendrocytes within four days. Testing on nerves lacking myelin, both on the lab bench and in diseased mouse models, showed the OPCs derived from the process flourished into oligodendrocytes and restored normal myelin within days, demonstrating their potential use in therapeutic transplants.
