The idea of parasitic worms causes a shudder in most people. The very thought of some wriggly segmented thing latching onto an internal organ and ransacking it for nourishment is not pleasant. But the scientists who study the creatures may be on to a whole new tack in the fight against type 1 diabetes. It turns out that people who suffer from parasitic worms experience an unexpected beneficial side effect: the worms exert control over the human immune system that seems to protect against several inflammatory diseases, including asthma, Crohn’s disease, multiple sclerosis, allergies, and… type 1 diabetes.
According to an article published in the April 9, 2010, online edition of Technology Review, produced by the Massachusetts Institute of Technology, both humans and animals afflicted with parasitic worms experience fewer allergies and immune diseases. And it’s true that as modern medicine and sanitation in wealthy nations have reduced the acquisition of parasitic worms, the incidence of allergies and inflammatory ailments has increased.
In the article, “Fighting Allergies by Mimicking Parasitic Worms,” one Tufts University researcher theorizes that the human association with parasitic worms goes so far back that the relationship between them became mutually beneficial rather than combative. In exchange for access to all the goodies of the human digestive system and other internal organs, the worms conferred immunity or resistance to several diseases that are almost epidemic in modern times.
Nobody knows just how the worms confer their protection. Scientists know that when people become infected by parasitic worms, it spurs an allergic response and levels of an antibody called IgE (immunoglobulin E) go up. In people without worms, excessive IgE binds with immune cells, making them spill their contents, including histamines, into the bloodstream, which leads to allergy symptoms. And yet, people with worms never reach this last stage. What interferes with it? One theory is that the worms produce an enzyme that interferes with receptors on the IgE antibody. When IgE attempts to bind to immune cells, it can’t, so the cells never receive the command to dump histamines.
Research into how worms are able to manipulate the human immune system is just beginning. It’s possible that future investigations could move along two tracks. In one, scientists may try to duplicate the beneficial effects of parasitic worms in patients who are not actually infected with worms. In the second, scientists may try to alter the worms so that they can live in humans and confer immunity without causing concomitant damage.
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