Scientists Claim Cure for Mouse Version of Multiple Sclerosis
PASADENA, Calif. (AP) _ A new treatment cures mice of a disease that resembles multiple sclerosis, but it will be at least 10 years before the method might be used to treat MS in humans, scientists said Thursday.
Multiple sclerosis is an often-crippling autoimmune disease, in which certain white blood cells in the body’s disease-fighting immune system run amok, attacking the body’s own nerve tissue.
As part of the new technique, scientists designed special antibodies, called monoclonal antibodies, to destroy the offending white blood cells that cause a similar disease in mice.
The method eventually could lead to techniques to prevent and treat not only multiple sclerosis but other human autoimmune diseases as well, including rheumatoid arthritis, lupus and myasthenia gravis, the California Institute of Technology said in announcing the findings.
″While we are quite excited about these results, I think it’s important to emphasize at the outset that we have not developed a cure for human multiple sclerosis or any other human autoimmune disease,″ said Caltech biologist Leroy E. Hood.
″In my opinion, our technique is at least 10 years away from human application,″ Hood said in a prepared statement, adding that he wanted to ″avoid raising false hope in those who suffer from this debilitating and quite serious disease.″
The study was conducted in Hood’s laboratory by research fellows Dennis Zaller and Gamal Osman, and by Osami Kanagawa, of Washington University in St. Louis. It will be published in next month’s issue of the Journal of Experimental Medicine.
Development of the new method to treat a mouse disease similar to human multiple sclerosis ″certainly is significant,″
If a treatment similar to the method used on mice can be developed for humans, ″that would be a major achievement,″ said Dr. George Ellison, a professor of neurology at the University of California, Los Angeles.
But he agreed with Hood that such therapy was years in the future.
To perform their experiments, the Caltech and Washington University scientists made mice sick with a disease called murine experimental allergic encephalomyelitis, or EAE.
The disease causes symptoms in mice similar to human multiple sclerosis, which is characterized by paralysis, muscle cramps and weakness, slurred speech, blurred vision, fatigue, difficulty in coordination, dizziness and loss of balance
To make the mice sick with EAE, the researchers injected them with a protein found in the sheaths that coat nerve cell fibers in the brain. The rodents’ immune systems then produced certain white blood cells, called helper T-cells, that attacked not only the injected protein but the protein in the rodents’ brains.
By studying the makeup of this type of T-cell in great detail, the scientists then designed monoclonal antibodies that, when injected into the sick mice, found and destroyed the disease-causing T-cells while leaving intact T-cells that protect the mice against other diseases.
Of five sick mice given the new treatment, three showed complete reversal of paralysis within two to seven days, and a fourth’s complete paralysis was reduced to slight paralysis of its tail. The fifth mouse died. Five other mice were not given the treatment, and their paralysis wasn’t reversed.
Related experiments in dozens of other mice showed that EAE could be prevented if they were injected with the monoclonal antibodies before they were injected with the protein that induced the disease.