Multiple Sclerosis (MS) May Damage Brain Years Before Symptoms Appear, Says New Study

A new study has found that multiple sclerosis (MS) begins damaging the brain several years before patients show any symptoms. The research, conducted by scientists at the University of California, San Francisco (UCSF), sheds new light on how the disease progresses and may pave the way for early diagnosis and prevention.

By studying blood samples, the researchers discovered that the body’s immune system starts attacking the brain’s protective covering, known as the myelin sheath, long before the disease is diagnosed. This sheath surrounds and protects the nerve fibres, and its destruction is one of the early signs of MS.

Until now, scientists were not sure when this damage began or which brain cells were involved. But by analysing over 5,000 proteins in blood samples from people with MS, the researchers were able to map the sequence of events that leads to the disease.

One of the key findings was the early rise of a protein called IL-3, which helps direct immune cells to the brain and spinal cord. This protein appears in the blood during a stage when significant damage is already happening in the brain, but the patient does not yet experience symptoms.

“We think our work opens numerous opportunities for diagnosing, monitoring, and possibly treating MS,” said Dr. Ahmed Abdelhak, assistant professor of Neurology at UCSF and co-lead author of the study, which was published in the journal Nature Medicine recently.

The study used blood samples from the U.S. Department of Defense Serum Repository, which stores blood from military personnel. Some of these individuals later developed MS, allowing researchers to track changes in their blood leading up to diagnosis.

They found that seven years before diagnosis, levels of a protein called MOG — which signals damage to the myelin sheath — were higher than normal. A year after that, another protein called neurofilament light chain increased, showing that the nerve fibres themselves were being damaged.

The researchers identified nearly 50 proteins linked to early MS. They have applied for a patent for a blood test based on the 21 most important ones.

“This gives us a much deeper understanding of how MS begins and progresses,” said Dr. Ari Green, senior author of the paper and head of UCSF’s Division of Neuroimmunology and Glial Biology. “It raises the hope that we might one day prevent MS, or at least protect patients from further brain injury.”

MS is a chronic disease that affects the central nervous system, often leading to disability. Early detection and intervention could significantly change how the disease is managed in the future, the researchers said.

Multiple Sclerosis (MS) Symptoms

MS can cause a wide range of symptoms, which vary from person to person and may change over time. Common early signs include numbness or tingling in the limbs, blurred or double vision, and fatigue. As the condition progresses, individuals may experience difficulty with walking, balance, or coordination.

Other frequent symptoms include muscle weakness, stiffness, or spasms, as well as slurred speech and dizziness. MS can also affect bladder, bowel, and sexual function. In some cases, cognitive changes may occur, such as problems with memory, attention, or concentration. Mood disturbances, particularly depression, are also commonly associated with the disease.

Situation In India

Over 2 lakh people in India are believed to be living with Multiple Sclerosis (MS), yet a large proportion remain undiagnosed. This is due to several challenges, including limited public awareness, inadequate access to neurologists—especially in rural areas—misinterpretation of early warning signs, and the absence of a national-level patient registry for MS.