|07.27.09 - Discovery to Aid in Future Treatments of Third-World Parasites.
Saranac Lake, NY – Scientists from the Trudeau Institute, along with collaborators from the Netherlands and Germany are researching how a part of our immune system responds to infections by parasites. According to an article just published in the Journal of Experimental Medicine, what they have learned may also lead to better treatments for allergic and asthmatic disorders.
Schistosomiasis, one of the most important of the neglected tropical diseases, is caused by infection with parasitic helminthes (worms). These parasites are long lived and dwell within blood vessels, where they produce eggs that become the focus of intense, chronic inflammatory responses. In severe cases, this inflammation is associated with life-threatening liver disease.
No vaccine is currently available to prevent schistosomiasis and options for treating the disease are largely limited to one drug, Praziquantel. Because of high rates of re-infection in drug-treated individuals, it is feared that widespread use may foster the emergence of drug-resistant variants, such as has seen with certain strains of tuberculosis.
Research just published in the Journal of Experimental Medicine explains that T cell responses, in the context of worm infections, are also associated with the clinical symptoms of allergic and asthmatic disorders. Thus, understanding the immune response to infection with parasitic worms might aid in improving treatments for allergies and asthma common in industrialized countries.
The body’s immune response to schistosome infection is coordinated by cytokines, small proteins secreted by immune cells that help regulate cellular activity. Due to their fundamental importance, cytokine research is a significant focus of research at the Trudeau Institute. Because cytokines travel through the body to relay critical information, it is difficult to identify the cells that produce them and to learn about their role.
Trudeau Institute scientists have devised laboratory models that help track the cells which produce the signature cytokine,”Th2” (T cells). These T cells aid in the production of the antibodies, which help mount a defense against infections with parasitic worms.
While it was previously known that the complex mixture of proteins released by schistosome eggs induce T cell responses and the production of antibodies, the specific molecule(s) responsible for these effects were unknown.
Earlier research from the laboratories of Markus Mohrs of the Trudeau Institute and Gabriele Schramm of the Research Center Borstel in Germany had shown that a protein called alpha-1 can support T cell responses but is unable to initiate them.
However, new findings, reported in the current issue of the Journal of Experimental Medicine, from an international study between Mohrs, Schramm, and Maria Yazdanbaksh of the Leiden University Medical Center in the Netherlands have now shown that omega-1, a single protein secreted from schistosome eggs, induces this T cell response in a laboratory test tube.
Importantly, using live laboratory models, the researchers have now shown that omega-1 alone is sufficient to generate T cell responses within the body. This will undoubtedly aid in unlocking the molecular pathways inducing T cell responses commonly elicited by infection with parasitic worms.
Ultimately, these new insights will help researchers in the field like Dr. Yazdanbaksh, who, in addition to her laboratory research, also oversees studies in schistosomiasis patients in Africa.
As with all basic research discoveries, incremental advances such as these may eventually lead to new treatments and therapies that will improve the day-to-day lives of the 200 million people around the globe currently afflicted by schistosomiasis.
Moreover, these Th2 responses, described above in the context of worm infections, are also associated with the clinical symptoms of allergic and asthmatic disorders. Thus, understanding the immune response to infection with parasitic worms might aid in ameliorating allergy and asthma common in industrialized countries.
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The Trudeau Institute is an independent, not-for-profit biomedical research organization, whose scientific mission is to make breakthrough discoveries leading to improved human health. Trudeau researchers are identifying the basic mechanisms used by the immune system to combat viruses like influenza, mycobacteria, such as tuberculosis, parasites and cancer, so that better vaccines and therapies can be developed for fighting deadly disease. The research is supported by government grants and philanthropic contributions.