Multiple sclerosis (MS) is considered an autoimmune disease that results in an abnormal immune system response in an individual’s body. This abnormal response damages Central Nervous System (CNS) tissues in a person’s brain, brain cortex, optic nerves or spinal cord.
Multiple sclerosis (MS) involves an immune-mediated process in which an abnormal response of the body’s immune system is directed against the central nervous system (CNS), which is made up of the brain, spinal cord and optic nerves. The exact antigen — or target that the immune cells are sensitised to attack — remains unknown, which is why MS is considered by many experts to be “immune-mediated” rather than “autoimmune.”
- Within the CNS, the immune system attacks myelin — the fatty substance that surrounds and insulates the nerve fibres — as well as the nerve fibres themselves.
- The damaged myelin forms scar tissue (sclerosis), which gives the disease its name.
- When any part of the myelin sheath or nerve fibre is damaged or destroyed, nerve impulses travelling to and from the brain and spinal cord are distorted or interrupted, producing a wide variety of symptoms.
- The disease is thought to be triggered in a genetically susceptible individual by a combination of one or more environmental factors.
- People with MS typically experience one of four disease courses, which can be mild, moderate or severe.
Immune cells which normally attack foreign substances called antigens such as a flu virus cross from the blood stream into a persons Central Nervous System and begin to attack neuron cells. Known as an exacerbation or more commonly an “MS Attack” immune cells attack a substance called myelin causing the tissue to swell and break apart. Myelin is a fatty substance that insulates tissue known as an axon.
If you consider a paradigm the myelin sheath is like an insulator covering an electrical wire. The Axon is similar to the actual copper wire. Myelin protects the axon and also assists in conducting electrical impulses between connecting nerve cells. The effect is that the electrical signals passing through nerves are weakened. If the axon itself is severed no electrical signals can pass at all.
Due to the loss of electrical signal strength other nerves may not receive proper signal strength, interpret signals incorrectly or not at all. The loss and misinterpretation of signals results in the wide variety of symptoms associated with multiple sclerosis.
This process of destruction of myelin is known as demyelination. Continued attack by the immune system cells can result in permanent damage to the axon or a complete severing of the axon.
As neuron cells are damaged areas of scar tissue are left behind. These damaged areas where scars exist are referred to as plaques or lesions.
The definition of multiple sclerosis is multiple scars.
Multiple sclerosis is a chronic, sometimes disabling disease of the central nervous system (CNS), the brain and spinal cord. Over 400,000 people estimated in the United States alone are affected by the disease and some 2.5 million people estimated globally.
Every person with multiple sclerosis has a unique pathology due to what areas of the Central Nervous System are damaged. Not too long ago MS was often misdiagnosed due to the wide range of symptoms that can occur as a result of the progression of the disease. Today it is estimated that as many as 10% of people who have MS still remain misdiagnosed.
Multiple sclerosis is considered a chronic disease as currently no cure for the disorder exists.
Because the exact antigen or reason for these immune-mediated attacks remains unknown, many experts prefer to label multiple sclerosis as and Immune Mediated Disease .vs an Autoimmune Disease.