Whether you have been diagnosed, in the process of being diagnosed, or wonder what it takes to get diagnosed with multiple sclerosis, it is likely that you have heard of LESIONS. Those scars (or plaques) which can be seen on MRI scans which show when the myelin has been damaged.
MYELIN is the fatty protein which creates an insulating sheath to protect nerve cells called AXONS. Myelin is part of the white matter in the brain and helps the electrical impulses of communication between the brain and parts of the body travel more quickly and efficiently. (see The Myelin Project for more information)
LESIONS occur where nerves have been demyelinated. So how does that happen?
The process of DEMYELINATION begins with inflammation. In the case of multiple sclerosis this happens in the CENTRAL NERVOUS SYSTEM (CNS) consisting of the brain and the spinal cord.
Think for a moment of a time when you accidentally cut a finger and decided against washing the wound immediately. The invaders of germs and bacteria are detected by the IMMUNE SYSTEM which sends in a team of specialized white blood cells, called LEUKOCYTES, to fight and destroy the invaders. Perhaps the wound became red and inflamed while the battle was underway.
In multiple sclerosis, a breach in the Blood-Brain-Barrier allows specialized white blood cells, called T-CELLS, to travel from the blood stream into the CNS. Once these ‘killer’ T Cells mistake myelin for foreign invaders and go on the attack, they produce CYTOKINES which destroy myelin and which also recruit MACROPHAGES to help destroy myelin and cut the nerve fibers.
Rest this post in its entirety:
Beginner's Guide to MS: What is a Lesion?