Scientists Find 'Cure' for Multiple Sclerosis By Turning Common Skin Cells into Working Brain Cells
Scientists have discovered a way to convert ordinary skin cells into myelinating cells, or brain cells that have been destroyed in patients with multiple sclerosis, cerebral palsy and other myelin disorders.
The research published in the journal Nature Biotechnology, may now enable "on demand" production of myelinating cells, which insulate and protect neurons to facilitate the delivery of brain impulses to the rest of the body.
The latest discovery is important because myelinating cells are destroyed and cannot be replaced in patients with multiple sclerosis, cerebral palsy, and rare genetic disorders called leukodystrophies.
Scientists explain that the new technique involves directly converting fibroblasts, a very common structural cell present in the skin and most organs into oligodendrocytes, the type of cell responsible for producing myelin, the fatty insulation necessary to allow neurons to communicate with one another.
"Its 'cellular alchemy,'" senior study author Paul Tesar, PhD, assistant professor of genetics and genome sciences at Case Western Reserve School of Medicine, explained in a news release. "We are taking a readily accessible and abundant cell and completely switching its identity to become a highly valuable cell for therapy."
Using a process called "cellular reprogramming" to manipulate the levels of three naturally occurring proteins, researchers were able to turn fibroblast cells into precursors cells that form oligodendrocytes (oligodendrocyte progenitor cells, or OPCs). With this newly discovered technique, researchers were able to generate billions of induced OPCs (iOPCs) that were capable of regenerating new myelin coating around nerves after being transplanted into mice.
Researchers hope the new technique could also be used to treat human myelin disorders. In myelinating diseases, oligodendrocytes, that make myelin, generally become damaged or dysfunctional. With the loss of functional oligodendrocytes, the protective myelin sheath that normally insulates and protects nerves is lost.
Researchers explain that a 'cure' requires the myelin coating to be regenerated by replacement oligodendrocytes. So far, OPCs and oligodendrocytes could only be reproduced from fetal tissue or pluripotent stem cells. While these techniques are valuable, they come with many limitations.
"With further optimization, this approach could provide a source of functional OPCs that will complement, and possibly obviate, the use of pluripotent stem cells and fetal cells in cell-based remyelinating therapies," researchers wrote in the study, according to U-T San Diego.
Researchers explain that the induced oligodendrocyte precursor cells, or iOPCs, are better than existing techniques because they only produce oligodendrocytes, whereas neural stem cells in induced neural stem cells produce other unwanted cells like neurons and astrocytes.
"The myelin repair field has been hampered by an inability to rapidly generate safe and effective sources of functional oligodendrocytes," co-author and myelin expert Robert Miller, PhD, professor of neurosciences at the Case Western Reserve School of Medicine explained in a statement. "The new technique may overcome all of these issues by providing a rapid and streamlined way to directly generate functional myelin producing cells," he said.
The next step is to show that the technique can be applied to human cells, and if successful, researchers believe the technique that transforms ordinary skin cells into functional brain cells could have widespread therapeutic application to human myelin disorders.