Stem cell therapy may be the new cure for myelin disorders
According to a study published in the journal Cell Stem Cell, researchers at the University of Rochester Medical Center (URMC) have made progresses regarding a possible cure for myelin disorders, which include multiple sclerosis and pediatric leukodystrophies. Multiple sclerosis is an inflammatory neurological disease for which there is no treatment. It is a disease that occurs in young patients and is characterized by progressive demyelination of the nervous system. Multiple sclerosis can give any neurological deficit: ataxia (difficulty walking), muscle paralysis, paresthesia, muscle weakness, dysphagia (difficulty swallowing), optic neuritis, etc.. It is a chronic disease that develops in acute relapses, which are treated with corticosteroids, and remissions, but there are cases when neurological deficits no longer recover.
The pathogenic mechanism of this autoimmune disease consists in multiple attacks against the myelin, which is part of nerve structure. It is not known what causes this autoimmune attack, although it is assumed that certain infections or intoxications are possible causes of multiple sclerosis. Myelin is a fatty material that has a role in nerve transmission, and therefore its loss leads to significant neurological deficits. It should be noted that loss of myelin also occurs in diseases other than multiple sclerosis, such as pediatric leukodystrophies which are some rare but fatal diseases.
Myelin is produced in the nervous system by some cells that are called oligodendrocytes, and the latter result from the proliferation of other cells called oligodendrocyte progenitor cell, or OPC. Researchers have long figured that targeted cell-based therapy may be the key for myelin disorders. In other words, if healthy OPCS could be transplanted into diseased or injured brain, these cells would produce new myelin. However, there have been several obstacles that have prevented researchers to put their idea into practice. One of them was to find a suitable source for such cells. But even if experiments with cells derived from tissue-specific and embryonic stem cells have not been successful, researchers still managed to finally find a solution, that is induced pluripotent stem cells. The risk of rejection is practically insignificant because these cells are taken from the recipient’s own skin.
Now researchers at the University of Rochester Medical Center (URMC) are the first who have been able to purify OPCS from hiPSCs and the first who have transplanted these cells into mice with a hereditary leukodystrophy. It seems that OPCS make a new myelin and, what is more interesting, is that hiPSC-derived cells do this more efficiently than tissue-derived cells created using OPCS.