Multiple sclerosis

What is multiple sclerosis?

Multiple sclerosis (MS) is a condition in which the nerves in the brain and spinal cord are damaged. Depending on where in the brain or spinal cord the damage occurs, MS can cause many different symptoms, including problems with vision, speech, chewing or swallowing; tingling or numbness or weakness in the arms or legs; bladder or bowel problems; loss of balance or dizziness; fatigue and problems with coordination; memory or thinking problems; etc.

MS affects about 2.5 million people worldwide, with women developing MS more commonly than men (~3:1). MS typically starts between the ages of 20 to 40 years, although it sometimes commences in childhood, and some people can get their first signs of MS after the age of 60. In most people, MS initially occurs in a pattern of attacks of disease (relapse), followed by resolution of the symptoms, at least in part (remission). In about 10-15% of people with MS, however, the disease will get progressively worse from outset, without the remission phase. During the last 30 years, several drugs that help to slow the progression of disease have been developed, and these are fairly effective in most people, although they do not cure the disease.

What causes multiple sclerosis?

MS commences due to an autoimmune attack on myelin, the insulating material that coats the nerve axons, the “electrical wires” that connect the nerve cells in the brain and spinal cord to other parts of the body.

During this autoimmune attack, a person’s immune system starts to “see” their myelin as being foreign, as if it were a virus or bacteria invading the body, and so it starts to destroy it. Once the myelin is damaged, the speed at which messages can pass from different parts of the body to the brain, or from the brain out to the rest of the body is slowed or stopped, and this is what causes the various symptoms that are seen in MS.

Breakdown of the myelin makes the nerve cells themselves more vulnerable to damage. Also, the autoimmune response occurring in the brain and spinal cord signals to other types of cells in the nervous system that there is something dangerous there, and they also start to produce molecules that can further damage the nerve cells, so the damage becomes self-perpetuating. Damaged nerve cells in the brain or spinal cord cannot be replaced, and leads to the progressive nature of MS. People with MS often carry some genes that predispose their immune systems to start the autoimmune attack, and some that allow the damage in the brain to get out of hand.

What MS research is being done at UQCCR?

UQCCR is working on several projects related to MS:

• We’re running a clinical trial to see if boosting a person’s own ability to kill immune cells that are infected with the Epstein-Barr virus (EBV) helps prevent disease progression in MS
• We’re testing to see if some of the drugs that are used to treat MS adversely affect a person’s ability to make a normal immune response to infectious agents against which they have been vaccinated, including influenza, varicella zoster, tetanus and SARS-CoV2.
• We’re using a humanized mouse model, in which the mouse’s immune system comes from a human donor, to dissect out exactly how the autoimmune attack on myelin happens - We’re growing human brain organoids (mini-brains-in-a-dish), which we can induce from skin cells of people with MS, to look at the effects of some of the gene mutations that occur in people with MS on how the brain develops and how the brain cells respond to the type of damage that occur in MS.