The immune system & MS

Find out what the immune system does and how MS affects it
How MS affects the immune system


This has been added to your Favorites

The immune system works as a defense in fighting diseases or infections. Multiple sclerosis (MS) is an autoimmune disease. This means that the body’s immune system attacks its own body parts, such as tissue or nerves, instead of protecting them as it should. We don't know why some people get MS and others don't, or why it starts in the immune system. The immune system triggers MS activity because it causes inflammation, or swelling, in the central nervous system (CNS).


Typically, to protect the body from harmful invaders, the immune system scans for foreign and potentially dangerous cells that can cause disease or infections. Once foreign cells are detected, the immune system will send its own disease fighting cells, or white blood cells, to fight off unwelcome visitors. Think of this as an army—the immune system is a commander and the white blood cells are soldiers protecting the territory (the body).


For people with MS, the immune system gets confused. Instead of protecting you from harmful cells, it attacks your CNS. Normally, a layer of cells called the blood brain barrier (BBB) prevents harmful substances from entering the brain and optic nerves. With MS, the white blood cells get through the BBB and mistakenly attack myelin, the white fatty substance that protects your brain nerves. This causes inflammation, which activates MS through new or changing lesions, relapses, and increased difficulty with moving around and doing physical tasks.

When discussing treatment with their healthcare provider, many MS patients may consider disease modifying therapies (DMTs) These are medications designed to target the immune system and affect the inflammatory process. Everybody’s experience is unique, so be sure to talk to your healthcare provider about finding a DMT that fits into your specific treatment plan.


Road Trip
Home & Travel

10 tips for traveling with MS

From Paul P.

Avoiding holiday stress for people living with MS
Daily life with MS

4 ways to help avoid holiday stress

From Gina F.

Maintaining Mindfulness at Work
Mental & emotional health

Maintaining mindfulness at work

From Biogen


Learn about MS and connect with others. Check out in-person and online events

From Biogen


MRI Tools and Technology
MS Education

Biogen partners with Siemens Healthineers

From Biogen

African Americans & MS
MS Education

MS among African Americans

From Dr. Williams


Want to know more about MS? Download our brochure today

From Biogen