Mimicking Little Worm’s Trick in a Bid to Treat Auto-Immune Diseases

By IAN JOHNSTON, science correspondent

A TINY worm could hold the key to curing diabetes, asthma, and hay fever and a host of other allergies, according to researchers at Edinburgh University.

The parasite, called a helminth, is able to fool the body’s immune system into ignoring it and the hope is that the same method could be used to cure or treat auto-immune diseases. Already, simply giving sufferers of inflammatory bowel conditions similar worms, which normally infect pigs and so die without reproducing in humans, has proved beneficial.

Professor Rick Maizels, of Edinburgh University’s school of biological sciences, has been awarded GBP 1.3 million by the Wellcome Trust to carry out research over five years to find a way of replicating the helminth’s protective cloak.

This could then be used to stop the immune system attacking the pancreas, as in diabetes, and to treat a whole host of other conditions caused when the body’s defence system malfunctions.

“Perhaps we can borrow a trick from parasites, and employ the molecules which suppress the immune system to treat these auto- immune disorders,” Prof Maizels said.

“The project therefore offers potential for new treatments of diseases in both the developed world and the disadvantaged countries of the tropics.”

The research team will focus on the role played by regulatory cells in the body, which tell the immune system not to attack harmless environmental molecules and the body’s own cells.

It is thought that the helminths, which range in size from about a millimetre to a centimetre, produce molecules that trigger a response in regulatory cells, tricking the body into switching off a response that would otherwise kill the parasites.

If that is the case, then infections could be cured, not by vaccination or drug treatment, but by reactivating the immune system.

“If we can find out how the parasite mobilises these regulatory cells to protect themselves from the immune system, we should be able to find a way to protect the pancreas,” Prof Maizels said.

“At the end of the five years, I think we should be able to replicate what the parasite does without needing to resort to giving someone a parasite infection.”

The immune system has evolved to ignore harmless foreign objects and target dangerous ones.

People can be infected with helminths without becoming ill, but over time accumulated damage leads to tropical diseases such as filariasis and schistosomiasis.

The research could also help to fight those conditions, which affect one in four of the global population.

The first findings of the study were reported in the Journal of Experimental Medicine.