Multiple sclerosis is an incurable autoimmune disease, meaning a person's immune system attacks the central nervous system, often causing disability. Now, a new study that scientists are hailing as a breakthrough showed microscopic nanoparticles were able to "stealthily trick" the immune system to stop attacking nerves.
The findings may even one day help treat other autoimmune diseases like Type 1 Diabetes or food allergies, according to the researchers.
"This is a highly significant breakthrough in translational immunotherapy," study co-author Dr. Stephen Miller, a professor of microbiology-immunology at Northwestern University Feinberg School of Medicine in Evanston, Ill., said in a press release. "The beauty of this new technology is it can be used in many immune-related diseases."
Autoimmune diseases occur when a type of white cell in the body's immune system called T-cells mistake the body's own tissues for foreign bodies, attacking them. Current treatments involve immune-suppressing medications which try to stall the immune system's destructive response, in the process leaving patients susceptible to infections and even cancer because of the reduced defenses.
In patients with multiple sclerosis, the immune system attacks myelin, a protective sheath of insulting material that encases nerve cells in the brain and spinal cord and helps cells communicate with each other. Disrupting these signals can result in symptoms ranging from mild limb numbness to paralysis and blindness.
For the research, published Nov. 18 in Nature Biotechnology, scientists developed nanoparticles that bound to antigens, substances that cause the immune system to produce antibodies targeting them. WebMD reports the nanoparticles were 200 times smaller than the thickness of a human hair and made from the same material used to create dissolvable stitches.
Using mice with relapsing remitting multiple sclerosis -- the most common form of the disease affecting 85 percent of patients with MS - scientists injected nanoparticles attached with myelin antigens into mice, which were then engulfed by immune cells.
However instead of destroying the cells, the immune system was tricked into thinking the nanoparticles were ordinary dying blood cells that didn't pose a threat, inhibiting the myelin-attacking T-cells and calming the autoimmune response. Mice didn't have future relapses or flare-ups for up to 100 days, which would be the equivalent of years in a patient with a MS.
The research was funded by the National Institutes of Health.
"Our approach resets the immune system so it no longer attacks myelin but leaves the function of the normal immune system intact," study co-author Dr. Stephen Miller, a professor of microbiology-immunology at Northwestern University Feinberg School of Medicine, said in a written statement.
"Unlike generalized immunosuppression, which is the current therapy used for autoimmune diseases, this new process does not shut down the whole immune system," added Dr. Christine Kelley, director of the division of discovery science and technology at the National Institutes of Health. "This collaborative effort between expertise in immunology and bioengineering is a terrific example of the tremendous advances that can be made with scientifically convergent approaches to biomedical problems."
The scientists next plan to test the approach in patients with multiple sclerosis, and in those with Type 1 diabetes or immunity-linked airway diseases such as asthma.
"There are just so many possible applications of this, it's fun to think about," study co-author Dr. Lonnie Shea, professor of chemical and biological engineering at Northwestern University in Evanston, Ill., told WebMD.
About 400,000 Americans have MS, and about 2.1 million people worldwide are affected. A person is diagnosed every hour, according to the National Multiple Sclerosis Society.