The Genome Of The Pig Whipworm Offers Insight Into How They Can Help Treat Immune Disorders
The very idea of ingesting medicines containing eggs of whipworms found in pigs' guts would be revolting enough to give some of us indigestion. But there is an increasing body of evidence suggesting that helminthic therapy, a therapy that requires inoculation with specific intestinal parasites, such as the pig whipworm, could actually cure diseases like inflammatory bowel disease, rheumatoid arthritis, multiple sclerosis, diabetes, and autism. Helminthic therapy recently got more backing after a group of researchers successfully mapped the genes of the pig whipworm parasite.
Why Autoimmune Diseases Are on the Rise in Western Countries
Most of the diseases that helminthic therapy targets are autoimmune diseases. While genetic predisposition does play a role, many researchers believe that autoimmune diseases are the curse of our times, thriving from our excessive compulsion to be hygienic. By keeping ourselves as clean as possible, we've also limited contact with bacteria and viruses that may have helped us develop a natural immunity against harmful ones — in some cases, this may have led autoimmune diseases to thrive.
All of this is based on a theory called the hygiene hypothesis, which states that these diseases are more prevalent in "germ-free" Western countries, as compared to developing countries. The solution to this problem, according to medical researchers, is to reintroduce helminths, or parasites, that allowed our ancestors to develop immunity against several diseases. One of these parasites is the pig whipworm, commonly found in the gut of pigs, although it can be found in other species too. Although the pig whipworm causes disease and loss in livestock, it does not cause disease in humans because they can only survive in the human body for a short time.
The researchers who decoded the worm's gene were led by Dr. Aaron Jex, of the Faculty of Veterinary Medicine at the University of Melbourne. In a press release, he said, "We know that humans infected with the harmless, 'pig whipworm' can have significantly reduced symptoms linked to autoimmune diseases. And now we have the genetic sequence of the worm, it opens the door to future human drug designs and treatment."
Contrarily, the '"human whipworm," Trichuris trichiura, is more harmful, and not good for use medicinally, as it causes roundworm infection. It affects about one billion people, who mostly live in developing countries, and causes dysentery, malnourishment, and impairment of physical and mental development.
Previous research has already shown the beneficial effects of introducing pig whipworms in the gut of patients with Crohn’s disease. It is believed that the worms regulate the body’s defenses, and prevent an autoimmune reaction that destroys the intestinal lining. The worm's genetic roadmap could lead to the development of several immune therapies. Co-author of the study, Professor Robin Gasser said that the genes tell us "about the proteins that this worm uses to interact with our immune systems. Knowing the worm's molecular landscape could be very useful in starting to understand autoimmune diseases in humans."
Source: Jex A, Gasser R, et al. Nature Genetics. 2014.