Parasitic Symbiosis as Therapy?

My mother always had a sense of humor and loved this poster. It was framed in our bathroom and was displayed prominently for all to see - I just couldn't imagine all of those little critters in my colon to keep me thin.

But now researchers in Argentina have reported in the Annals of Neurology that intestinal parasites may help remit bouts of multiple sclerosis:

(BBC) The scientists said it was possible that the parasites were able to influence the production of T-cells - cells which "dampen down" immune reactions within the body, both ensuring their success, and reducing "autoimmune" illnesses such as MS.

"To the best of our knowledge, this is the first study to report chronic exposure to parasites as an environmental factor altering the course of MS in humans," they wrote.

How is it thought to work? By changes in the immune system thought to be induced by the presence of the parasites:

Myelin basic protein-specific T cells cloned from infected subjects were characterized by the absence of IL-2 and IL-4 production, but high IL-10 and/or TGF-(beta) secretion, showing a cytokine profile similar to the T-cell subsets Tr1 and Th3.

Any parent who has had a child with pinworms knows that this therapy will never fly long-term, but perhaps a better understanding of how these worms manipulate the immune system will lend a jumpstart to understanding this disease.

-Wes