IBD causing bacteria discovered in mice

Bacteria that cause weight loss and intestinal inflammation have been identified in the microbiome of mice used to study Inflammatory Bowel Disease (IBD).

Researchers from Hudson Institute of Medical Research, the Wellcome Sanger Institute, the University of Cambridge and collaborators, have discovered and named two new strains of bacteria in the microbiome of mice that cause Inflammatory Bowel Disease (IBD) symptoms.

Potential change in how IBD is studied

The study, published in Nature Microbiology, could force changes in the way IBD is studied, because it shows that these bacteria are commonly found in mice that are used in this type of research.

Dr Samuel Forster, first author from the Hudson Institute of Medical Research, Australia, said: “Mouse models are used widely to uncover more information on the development and treatment of Inflammatory Bowel Disease, however our research shows that the microbiome of these mice could impact on the results from these studies.”

Inflammatory Bowel Disease, otherwise known as IBD, is a lifelong condition that impacts around 6.8 million people globally each year¹. It occurs when there is chronic inflammation of the gastrointestinal tract and includes ulcerative colitis and Crohn’s disease¹. IBD is considered a chronic condition, and when it flares up, it can cause debilitating symptoms that substantially reduce a patient’s quality of life.

Understanding the microbiome key to treating IBD

While the exact cause of IBD is unknown, it has been suggested that in some individuals the immune system reacts to the naturally occurring bacteria in the gut, highlighting the importance of studying the microbiome in understanding and treating this condition.

“While there are currently methods in place to reduce the impact of known disease-causing bacteria on studies, we have highlighted that there are bacteria that were previously unknown, and therefore not adjusted for. We hope that our research helps in the study design and interpretation of similar work in the future.”

While specific protocols have been established to control any effects that could be caused by known bacterial pathogens in the mouse microbiota, there is still a broad range of bacteria that need to be classified, identified and understood. It is important to understand the mouse microbiota and its impact on disease, in case this influences results and has implications for any further research.

1. GBD 2017 Inflammatory Bowel Disease Collaborators. (2017) The global, regional, and national burden of inflammatory bowel disease in 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017. DOI:10.1016/S2468-1253(19)30333-4