Researchers may have pinpointed a molecule that causes multiple sclerosis, Science Mag reported this afternoon. The researchers have been exploring the theory that multiple sclerosis is triggered by a self-antigen, which is a normal molecule in the body that the immune system mistakes for an antigen and mobilizes to destroy it. Research has focused on proteins in myelin, a fatty substance that creates a sheath around the nerves to insulate them, but have been unable to pinpoint and isolate a potential self-antigen until now.
Multiple sclerosis (MS) is a disease caused by an autoimmune response to self-antigens, in which the body’s own immune system attacks the myelin sheath that insulates the central nervous system. When the myelin and nerve fibers are damaged, the electrical messages along the central nervous system become altered or broken. The damaged areas develop scar tissue that gives the disease its name.
Multiple sclerosis typically causes lesions on areas in the central nervous system, particularly in the nervous system’s “white matter” cells. White matter cells carry signals through the central nervous system to “gray matter” cells, which process the information. As the immune system begins to attack the myelin sheath, the invasion of T cells to the affected area causes inflammation around the nerve center, often resulting in intense pain and other symptoms. Finally, the victim will experience a breakdown in the blood-brain barrier, the part of the capillary system that prevents T cells from entering the central nervous system. After the T cells enter the nervous system and the blood-brain barrier repairs itself, the T cells become trapped inside the brain and disrupt numerous bodily functions.
The most common symptoms of multiple sclerosis are overwhelming fatigue, visual disturbances, altered sensations, and mobility problems. As progressive damage to the central nervous system can affect every process in the body, the symptoms can be wildly unpredictable, and the severity of the symptoms can differ from person to person and moment to moment. They may go into a remission and either disappear or return, or symptoms may persist and get worse over time.
According to the National MS Society, about a third of people diagnosed with multiple sclerosis are unable to walk, while many who retain their mobility may need an aid such as a cane or a scooter.
There is currently no cure for multiple sclerosis. The identification of the self-antigen that causes multiple sclerosis could lead to a bevy of new treatments for the disease, and potentially allow for a preventative or cure-based treatment.
“The work is monumental, and it’s tantalizing,” said neuroimmunologist Hartmut Wekerle of the Max Planck Institute of Neurobiology.