Scientists have discovered why some people may be protected from harmful parasitic worms naturally while others are not in what could lead to new therapies for up to one billion people worldwide.
Parasitic worms are a major cause of mortality and morbidity, particularly in the Third World, as well as domestic pets and livestock across the globe.
Now, University of Manchester researchers have, for the first time, identified a key component of mucus found in the guts of humans and animals that is toxic to worms.
“These parasitic worms live in the gut, which is protected by a thick layer of mucus,” explained Dr David Thornton, from the University’s Wellcome Trust Centre for Cell Matrix Research. “The mucus barrier is not just slime, but a complex mixture of salts, water and large ‘sugar-coated’ proteins called mucins that give mucus its gel–like properties.
“In order to be able to study these debilitating worm diseases, we have been using a mouse model in which we try to cure mice of the whipworm Trichuris muris. This worm is closely related to the human equivalent, Trichuris trichiura. We previously found that mice that were able to expel this whipworm from the gut [when the stomach] made more mucus. Importantly, the mucus from these mice contained the mucin, Muc5ac. This mucin is rarely present in the gut, but when it is, it alters the physical properties of the mucus gel.”
Dr Sumaira Hasnain, the lead experimentalist on the project, added: “For the first time, we have discovered that a single component of the mucus barrier, the Muc5ac mucin, is essential for worm expulsion. Our research may help to identify who is and who isn’t susceptible to parasitic worms, and it may eventually lead to new treatments for people with chronic worm infections.”