Scientists Develop New Mouse Model to Study Crohn's Disease

Researchers at Canada's McMaster University have taken an alternative path in trying to uncover more information about Crohn's disease. They have developed a new mouse model to study the digestive disorder.Mice have often been used to study this illness. Researchers frequently studied genetically modified mice. These mice died about a week after being injected with inflammation-causing chemicals in an attempt to figure out the relationship between inflammation and the presence of the bacteria E. coli .Many bacteria reside in the gut. Some are beneficial to digestion. The Mc Master researchers elected to study an E. coli variant dubbed adherent-invasive E. coli, or AIEC. This variant has been linked to Crohn's disease in humans.The scientists developed a new mouse model that showed that E. coli linked to Crohn's had the potential to cause long-term infection in the gut of a mouse. The mice they studied did not die quickly, but developed a chronic gut inflammation similar to that in human Crohn's patients.The new model allows researchers to study the effects of long-term infection. It provides an opportunity to determine the effects of chronic E. coli colonization on the immune system and how that might affect the development of disease. The team successfully developed a model of chronic colonization in five lines of non-modified mice.Crohn's disease and ulcerative colitis are the two primary types of inflammatory bowel disease (IBD). Crohn's can occur anywhere in the digestive tract between mouth and anus, but most often develops in the intestines, where the ulceration it causes can affect all layers of tissue. According to the Mayo Clinic, since experts have found no cure for Crohn's, treatment focuses on managing its symptoms and trying to create a remission.The Crohn's & Colitis Foundation of America says that around 700,000 Americans suffer from this chronic disorder, which typically appears between ages 15 and 35. It affects roughly equal numbers of males and females. Although experts haven't pinpointed a cause, they suspect a combination of genetics, environmental factors, and a faulty immune system.The presence of IBD in other family members of Crohn's patients is one reason scientists suspect a genetic basis. However, many patients with the disorder report no other incidence of IBD in their families.This knowledge has led scientists to dig deeper into a known microbiological link to the illness. They already know that both human and animal studies have suggested that certain bacteria are necessary for the signs of Crohn's disease to appear.The Manchester team hopes to eventually understand the human host's response to bacteria linked to Crohn's. This will initially involve more work with the new mice model. The researchers hope to determine which genes are present in the bacteria to make it invasive, how it colonizes for extended periods, and why it has a pro-inflammatory nature.

Vonda J. Sines has published thousands of print and online health and medical articles. She specializes in diseases and other conditions that affect the quality of life.

Source: Medical News Today