One study found that experimental stem cell transplants are safe and possibly effective in children with a rare genetic brain disease. Another study in mice showed that these cells are capable of transforming into, and functioning as, the healthy cell type. The stem cells used in the two studies were developed by study sponsor StemCells, Inc.
Both papers appear online in Science Translational Research.
The work, while still in its infancy, may have far-reaching implications for the treatment of many more common diseases that affect the brain and nervous system.
Researchers out of the University of California, San Francisco (UCSF), looked at the how neural stem cells behaved when transplanted into the brains of four young children with an early-onset, fatal form of Pelizaeus-Merzbacher disease (PMD).
PMD is a very rare genetic disorder in which brain cells called oligodendrocytes can’t make myelin. Myelin is a fatty substance that insulates the nerve fibers of the brain, spinal cord, and optic nerves (central nervous system), and is essential for transmission of nerve signals so that the nervous system can function properly.
In multiple sclerosis, the myelin surrounding the nerve is targeted and damaged by the body’s immune system.
The new study found that the neural stem cell transplants were safe. What’s more, brain scans showed that the implanted cells seem to be doing what is expected of them -- i.e. making myelin.
Researchers compared treated areas of participants' brains with untreated areas. "The study goes beyond safety and we see some effects in the transplanted region that are consistent with the appearance of myelin, at one year,” says study author David H. Rowitch, MD, PhD. “It is not definitive, but it is suggestive.” He is a professor of pediatrics and neurological surgery at UCSF, and is the chief of neonatology at UCSF Benioff Children’s Hospital.
PMD is rare, but other diseases that affect the myelin, such as MS, are more common.