In autoimmune conditions, the body turns against itself. Now, researchers are trying an age-old trick to teach the immune system that the body’s cells and proteins are not the enemy.
Western medicine has struggled to find effective treatments for autoimmune diseases. Grave’s disease, lupus, and multiple sclerosis: None has a cure or a simple, universally effective treatment.
For 100 years or more doctors have hoped that the kind of desensitization used to treat allergies — where the immune system learns to tolerate larger and larger doses of the problem substance — would also work for autoimmune diseases. Unable to get the idea to work in practice, doctors have turned to dampening the patient’s entire immune response with medications.
But a new study,
University of Bristol researchers proved their method in a mouse model of multiple sclerosis (MS). They started with a “miniscule amount” of myelin, the nerve-insulating protein that the immune system mistakenly attacks in MS. Then they gradually added more, said Graham Britton, a biologist and one of the paper’s authors.
The immune system became progressively less reactive to the myelin. The same cells that had attacked myelin were retrained to recognize it as a friend, rather than a foe.
“You can convert these cells, which are being aggressive and attacking part of the body, to being protective and acting in a way to communicate with the other parts of the immune system to dampen the attack and hopefully lead to an improvement in the disease symptoms,” Britton said.
The concept is straightforward, but the devil is in the details, according to Britton and Dr. Bruce Bebo, associate vice president of research discoveries for the National MS Society.
“That concept of introducing very specific immune tolerance to myelin targets is a leading technology for trying to help reduce the symptoms of MS,” said Bebo. “This paper is not definitive, but it is adding to our knowledge about strategies for reducing immune responses to myelin and could ultimately result in strategies to help stop MS.”
The key to success was precision dosing and the way the researchers prepared the myelin.
“The main hurdle up to now is the way that you give that molecule, the form that you give it in,” said Britton. By slicing off bits of the myelin protein small enough to be water-soluble, Britton’s team made them more manageable for the immune system.
The study has kindled hopes that the same method could work for other autoimmune diseases. There’s reason to think that the same technique would work for other conditions where doctors know exactly what triggering substance, or antigen, the immune system is attacking by mistake.
“For MS, the target of the attack is really well observed. But with some diseases it’s a lot less clear what those antigens are,” Britton cautioned.
Even in MS, getting the method to work for individual patients might pose additional problems, according to Bebo.
“We know the target is myelin and probably proteins, but the target is probably different in different people with MS, and it changes over time. It’s a moving target,” he said. That would mean that each patient might require a slightly different regimen to retrain their immune system.
Even so, the method is likely to lead to much more research into treatments for MS, Grave’s disease, and other autoimmune conditions. And that’s what patients are waiting for.