Scientists at the University of Edinburgh have discovered that the puny little worm H Polygyrus induces regulatory T cells and effectively suppresses the immune system. The plan now is to discover the mediator(s) responsible for this effect:
University of Edinburgh scientists have discovered that helminth parasites can exploit an ‘Achilles heel’ in our immune system, tricking the body’s defences into switching themselves off.
To find out how the worms do this, the team are focusing on the role played by ‘regulatory cells’, which fulfil a policing role that protects our bodies. These cells decide when to stop the immune system from attacking the body’s own proteins, and also prevent it from wasting time attacking harmless environmental molecules.
It is thought that helminths produce molecules that trigger a response in regulatory cells similar to the one that prevents autoimmunity, fooling the body into switching off the 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.
It is the first time such a concept has been explored to curb the tropical diseases caused by helminths – such as filariasis and schistosomiasis – which affect one in four of the global population.
The study – the first findings of which are reported in the Journal of Experimental Medicine – could also help growing numbers of people in the developed world who have autoimmune conditions such as diabetes, and allergies like asthma and hay fever.
Again, the key is identifying the molecules that helminths produce in order to influence regulatory cell activity. If scientists can understand how these molecules trigger suppression of the immune system, they might also employ the molecules to stop the immune system from attacking the body’s own cells – which is what happens in diseases caused by over-active immune responses.
Professor Rick Maizels, of the University of Edinburgh’s School of Biological Sciences, has been awarded £1.3 million by the Wellcome Trust to conduct the research.
“Perhaps we can borrow a trick from parasites, and employ the molecules which suppress the immune system to treat these disorders,” he explains.
“The project therefore offers potential for new treatments of diseases in both the developed world and the disadvantaged countries of the tropics.”
The press release…