Eye View 

by David Charbonneau

We need to research MS by as many means as possible

 

September 2, 2010


Nova Scotia is the latest province to support a clinical trial to treat multiple sclerosis with a controversial new procedure developed by Italian doctor Paolo Zamboni. He contends that MS is caused by narrowed or blocked veins in the neck which leads to a buildup of iron in the brain.

A number of provinces now support a national randomized clinical trial of the so-called liberation treatment. It would be fantastic if the treatment worked although it will be too late for my cousin who died young of the dreadful disease. MS which not only affects bodily functions such vision, hearing, memory, balance and mobility; it also leads to depression, family breakup, and financial loss.

While liberation treatment may prove miraculous, it's too soon to throw out decades of research which indicate that MS is an autoimmune disease: something triggers the immune system to run wild and attack our own tissues. This reaction results in inflammation and damage to nerve fibers.

Where you live matters. People who grow up near the equator rarely get it and oddly enough, they carry that protection even if they travel elsewhere. Canadians have one of the highest rates of in the world. At first glance it might seem that the sunshine vitamin, vitamin D, must be a factor but no link has been established. And Canada's Innu live as far as you can get from the equator and yet have a low incidence of MS. Childhood infection seems to play a role.

Dr. Herve Perron explores these childhood infections, as reported in Discover science magazine. He has spent years trying to find the lethal trigger that switches on the autoimmune attack. At first he thought it must be a virus but when none was found, Dr. Perron switched his hunt to retroviruses. Retroviruses (literally, backward viruses) work in reverse; they reproduce by making DNA from RNA. Once they hijack a cell's resources, they start cranking out duplicates. The most infamous retrovirus is HIV which causes AIDS, another causes cancer.

Research is labour intensive. For eight years, Dr. Perron examined the spinal column fluids of MS patients in search of the elusive MS retrovirus. Toiling away in an airtight biohazard lab, he spent his waking hours in masks, gloves and disposable scrubs.

 

 No one could have predicted what he found in 1997. External retroviruses were not the problem. Instead, the culprit was an insidious virus that is dormant within us all; right in our DNA. All of Dr. Perron's protection against an external retrovirus while working in the lab would not have shielded him from MS.

How did these embedded retroviruses get inside each and every one of us? It turns out that external viruses have slowly crept into our DNA as hitchhikers. In the last 100 million years there have been about 50 viral infections which have left snippets of their DNA inserted in ours. This explains the mystery of what first seemed to be "junk DNA;" large segments that had no observable use at all. While it's not junk, it's not exactly useful either. Forty per cent of our DNA is made up of viral sequences that we have picked up over the years.

That doesn't mean everyone is equally susceptible to MS. Serious childhood infection seems to play a role by causing these dormant viral sequences, called endogenous retroviruses, to spring to life. That infection upsets a child's immature immune system so that endogenous retroviruses form. If the child survives the initial infection they remain dormant until triggered.

That explains why childhood susceptibility to MS occurs in northern climates, especially winter flu season. Those dormant retroviruses are carried throughout life even if the person later moves to an equatorial climate.

In susceptible adults, environmental factors trigger a wild immune response involving the dormant retroviruses that attacks the body's own nervous system characterized by MS. Smoking, for example, seems to be a trigger.

Dr. Perron has founded a biotech start-up company that hopes to create an antibody that neutralizes activated retroviruses. So far, "We have terrific effects," says Perron with good results from using the antibody in lab mice with MS. A clinical trial could take place as early as next year.

No treatment of MS should be dismissed without clinical trials but it would be a shame to place all our research eggs in one basket.

 David Charbonneau is the owner of Trio Technical.
He can be reached at dcharbonneau13@shaw.ca
 





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