Brain Cell Transplants Can Repair MS Damage
By: Sai Srihaas Potu
Multiple sclerosis (MS) is a debilitating disease that affects the central nervous system. In MS, the immune system attacks the protective sheath (myelin) that covers nerve fibers and causes communication problems between your brain and the rest of your body. Eventually, the disease can cause permanent damage or deterioration of the nerves. Now, a new study from the University of Rochester has shown that its effects may be prevented and even reversed in mice, by transplanting certain brain cells.
This study shows that when specific human brain cells are transplanted into animal models of multiple sclerosis and other white matter diseases, the cells repair damage and restore function. The study provides one of the final pieces of scientific evidence necessary to advance this treatment strategy to clinical trials.
Researchers have developed techniques to manipulate the chemical signaling of embryonic and induced pluripotent stem cells to create glia. A subtype of these, called glial progenitor cells, gives rise to the brain’s main support cells, astrocytes, and oligodendrocytes, which play important roles in the health and signaling function of nerve cells.
In multiple sclerosis, an autoimmune disorder, glial cells are lost during the disease. Specifically, the immune system attacks oligodendrocytes. These cells make a substance called myelin, which, in turn, produces the “insulation” that allow neighboring nerve cells to communicate with one another.
As myelin is lost during disease, signals between nerve cells become disrupted, which results in the loss of function reflected in the sensory, motor, and cognitive deficits. In the early stages of the disease, referred to as relapsing multiple sclerosis, the lost myelin is replenished by oligodendrocytes. However, over time these cells become exhausted, can no longer serve this function, and the disease becomes progressive and irreversible.
Researchers have demonstrated that when human glia progenitor cells are transplanted into adult mouse models of progressive multiple sclerosis, the cells migrated to where needed in the brain, created new oligodendrocytes, and replaced the lost myelin. The study also showed that this process of demyelination restored motor function in mice. The researchers believe this approach could also be applied to other neurological disorders, such as pediatric leukodystrophies – childhood hereditary diseases in which myelin fails to develop – and certain types of stroke affecting the white matter in adults.
The study has found that behavioral training in mice promoted the regeneration of myelin sheaths from newly formed and mature oligodendrocytes to aid in the repair of damage to the nervous system.
This proves that when specific human brain cells are transplanted into animal models of multiple sclerosis and other white matter diseases, the cells repair damage and restore function. This provides one of the final pieces of scientific evidence necessary to advance this treatment strategy to clinical trials.
Currently, there is no cure for multiple sclerosis. Treatment typically focuses on speeding recovery from attacks, slowing the progression of the disease, and managing MS symptoms.
Their findings offer a potential new target for therapeutic interventions for patients with neurologic disabilities, such as those caused by MS, which is a progressive, degenerative disease that affects the ability of the brain to communicate with the rest of the body.