The prevailing hypothesis concerning the development of allergy and probably autoimmune disease is the "hygiene hypothesis," which states that people in "hygienic" societies have higher rates of allergy and perhaps autoimmune disease because they -- and hence their immune systems -- have not been as challenged during everyday life by the host of microbes commonly found in the environment.
The study suggests that an overly hygienic environment could simultaneously increase the tendency to have allergic reactions and the tendency to acquire autoimmune disease, despite the fact that these two reactions represent two different types of immune responses.
The researchers added that their experimental model, which compares specific immune system responses of wild rodents to laboratory rodents, could open up a new approach to studying human disease and allergies that complements traditional scientific studies.
"Laboratory rodents live in a virtually germ- and parasite-free environment, and they receive extensive medical care -- conditions that are comparable to what humans living in Westernized, hygienic societies experience," said William Parker, Ph.D., an assistant professor of experimental surgery and senior member of the study team. "On the other hand, rodents living in the wild are exposed to a wide variety of microbes and parasites, much like humans living in societies without modern health care and where hygiene is harder to maintain."
The researchers published their results early on-line in the Scandinavian Journal of Immunology. The research
Source:Duke University Medical Center