Natural parasites

Infection biologists at FAU discover therapeutic potential in parasitic worms

Erlangen infection biologists have gained a new insight into how our body can be better protected from allergies and autoimmune responses: a working group headed up by David Vöhringer, Professor of Infection Resistance and Tolerance at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and head of the Infection Biology Department at Erlangen University Hospital’s Microbiology Institute, has been able to verify that parasitic worms can have a positive effect on certain types of T helper cells. Their findings were recently published in the renowned Journal of Immunology (www.jimmunol.org). Erlangen researchers now aim to investigate how the worms influence the immune system in an attempt to provide new approaches to the development of effective medicines.

Our immune system protects us from a multitude of pathogens, and T helper cells play a crucial role in this process. They are involved in the activation of scavenger cells and the formation of antibodies which fight invading bacteria and viruses in the body. Normally, T helper cells do not attack the body’s own tissue – sufferers of autoimmune diseases such as multiple sclerosis or Type 1 diabetes, however, appear to be lacking such tolerance: in such cases Th1 and Th17 T helper cells form, which both trigger a strong inflammatory reaction.

Interestingly, autoimmune diseases are less common in countries with lower hygiene standards. “One hypothesis behind this is that a parasitic worm infection – common in these countries – can protect against undesired responses of the immune system such as allergies and autoimmunity”, explains Prof. Vöhringer. However, at this point in time very little is known about exactly how this happens.

The working group headed by Prof. Vöhringer has now gained new insight into a possible mechanism. Using mice infected with Nippostrongylus brasiliensis parasitic worms, researchers were able to show that it is possible to reprogramme the Th1 and Th17 cells responsible for autoimmune processes into Th2 cells. Th2 cells release messengers which have an inhibiting effect on Th1 and Th17 mediated immune responses. “This now means that for the first time we have concrete evidence that parasitic worms have a positive effect on the reprogramming of T cells and in turn on our immune system”, says Prof. Vöhringer.

The Erlangen infection researchers are now investigating how this unexpected flexibility of T cells can be of therapeutic use in the future. To do so, the next step is to separate the parasite’s accountable components. The medium-term goal is to support the pharmaceutical industry in the development of effective medicines against autoimmune diseases.

Further information for the media:

uni | media service | research No. 3/2012 on 24.1.2012