Scientists in California have found what they say is the mechanism by which multiple sclerosis causes damage. According to the study, a protein found in the blood that gets into the brain goads the immune system into attacking brain and nerve cells. This causes the characteristic damage of MS.
“To successfully treat MS, we must first identify what triggers the disease and what enables its progression,” said Katerina Akassoglou, PhD, a researcher at the Gladstone Institutes and a professor of neurology at the University of California, San Francisco, in a statement. “Here, we have shown that the leakage of blood in the brain acts as an early trigger that sets off the brain’s inflammatory response—creating a neurotoxic environment that damages nerve cells.”
In other words, the protein her lab discovered is involved, fibrinogen, appears to set off an immune response. This leads to the body attacking its own cells, particularly those in the myelin sheath that protects the nerve cells, as though they were invaders. Successful treatment depends on preventing the body from killing the cells.
Fibrinogen is a protein that is used in blood coagulation. It is not normally found in the human brain, and plays no role there. However, images of the brains of multiple sclerosis patients found this protein, which had gotten through a flaw in the barrier that prevents things in the blood other than oxygen from getting into the brain. Once the fibrinogen is in the brain, the cells responsible for initiating an immune response activate, leading to nerve cell damage.
By modifying the genes of fibrinogen proteins, the researchers were able to keep the immune cells from reacting in animal models. It remains to be seen if the same technique would work in human patients.
Another treatment approach involves nanoscale particles that hide the targeted cells from the body’s overactive defense system. This protects the healthy cells with a sort of recursive camouflage, making non-threatening cells that are misinterpreted as threatening appear to be non-threatening cells that are correctly recognized as non-threatening, protecting them from the immune system.