Reseachers Isolate One Cause of Multiple Sclerosis

California researchers said Thursday that they have discovered one cause of multiple sclerosis, a finding that may lead to new therapies for the disease.

MS afflicts an estimated 250,000 people in the United States. The disease forces the body’s immune system to attack its central nervous system. It typically afflicts people between 20 and 40 years of age.

Dr. Lawrence Steinman, a neurologist at Stanford University, reported in the journal Nature that he and his co-workers isolated highly specific white blood cells that attack the myelin coating around nerves, effectively creating a short circuit that impairs nerve transmissions.

The discovery opens the door to the possibility of developing drugs that would selectively interfere with the attack on these cells without impairing the immune system’s ability to fight off infections.

Physicians have tried using immunosuppressant drugs such as those used in transplants to stop the immune attack, but the side effects have proved more severe than MS itself. Steinman, also head of immunology research at Neurocrine Biosciences in San Diego, said the company is progressing rapidly in development of simple proteins that could bind with the newly discovered immune cells, or T-cells, to prevent them from attacking myelin.

The Stanford team found the T-cells in the brains of eight of the 16 MS patients they studied. But the fact that they did not observe the same T-cells in the other eight patients means “they have not found the cause of multiple sclerosis but simply one of many possible causes,” said Stephen C. Reingold, vice president for research and medical programs of the National Multiple Sclerosis Society.

Steinman described the protein therapy Neurocrine is developing as “the most practical approach with the shortest development time before proceeding to clinical trials.”