Multiple Sclerosis Breakthrough: Nanoparticle Halts Disease in Mice

A scientific breakthrough has arrested the development of multiple sclerosis in mice and has implications for a new treatment for the degenerative disease.

Researchers at Northwestern University in Illinois found a new nanoparticle that tricks and resets the immune systems of mice with MS.

MS is a neurological disease that affects around 100,000 people in the UK. It is mostly diagnosed in people who are aged between 20 and 40.

A substance called myelin protects nerve fibres in the central nervous system. When people have MS, their immune system, which would normally fight off infections, mistakes myelin for a foreign body and attacks it.

These attacks damage the myelin and strips it of nerve fibres. Over time, this nerve damage causes the accumulation of disability.

The new nanoparticle works by delivering an antigen that makes the immune system stop its attack on myelin and halt relapsing remitting MS in mice. Around 80 per cent of people with MS are diagnosed with the relapsing remitting form of the disease.

People who suffer from relapsing remitting MS have symptoms ranging from mild limb numbness to paralysis or blindness.

The biodegradable nanoparticle also has implications for the treatment of Type 1 diabetes, asthma and food allergies.

Current therapies for MS suppress the entire immune system, leaving patients vulnerable to infections and higher rates of cancer. The nanoparticle, however, was attached to myelin antigens and injected into the mice, allowing the immune system to reset itself to normal and stop attack on myelin.

Stephen Miller, a corresponding author of the study, said: "The holy grail is to develop a therapy that is specific to the pathological immune response, in this case the body attacking myelin. Our approach resets the immune system so it no longer attacks myelin but leaves the function of the normal immune system intact.

"We administered these particles to animals who have a disease very similar to relapsing remitting multiple sclerosis and stopped it in its tracks.

"We prevented any future relapses for up to 100 days, which is the equivalent of several years in the life of an MS patient."

The researchers used a method similar to one currently being tested in MS patients with one major difference. The human trial used the patient's own white blood cells to deliver the antigen, which is a costly and labour intensive procedure.

Researchers wanted to find out if nanoparticles could be as effective as delivery vehicles as white blood cells are. They discovered they were - meaning a much cheaper and easier means of delivering MS treatments could be developed.

"This is a highly significant breakthrough in translational immunotherapy," Miller said.

"The beauty of this new technology is it can be used in many immune-related diseases. We simply change the antigen that's delivered."

Lonnie Shea, who also authored the study, said: "This is a major breakthrough in nanotechnology, showing you can use it to regulate the immune system."