Cedars-Sinai Researchers Identify Over 100 Types of Intestinal Fungi

Posted on June 8, 2012

Gut Fungi Microscope Image

Cedars-Sinai researchers say their examination of the fungi in the intestines suggests an important link between these microbes and inflammatory diseases such as ulcerative colitis. Researchers at Cedars-Sinai's Inflammatory Bowel and Immunobiology Research Institute identified and characterized the large community of fungi inhabiting the large intestine. The research paper was one of several published in a special section on gut microbiota in a recent issue of Science magazine. Microscope images of an intestinal fungus are pictured above and below.

The digestive tract is home to a large number of microorganisms. There are an estimated 100 trillion bacteria residing in the gut. Some are beneficial. They aid in digesting food, produce necessary vitamins and suppress the growth of harmful microbes. Other microorganisms harm the body. They contribute to illnesses such as Crohn's disease, colitis and obesity. Fungus in the gut is even less understood than bacteria. There are at least 100 types of gut fungi.

Gut Fungi Microscope Image 2

David Underhill, PhD, associate professor and director of the Graduate Program in Biomedical Science and Translational Medicine, who led the study, says, "It's long been recognized that fungi must also exist in the gut, but we're among the first to investigate what types, how many, and whether they're important in disease. We were truly stunned to see just how common fungi are, identifying more than 100 different types."

To determine how fungi contribute to inflammatory disease, the study homed in on a protein called Dectin-1, which is produced by white blood cells and used by the immune system to detect and kill fungi. In an animal model of the disease, researchers found that the protein is important in protecting against inflammation caused by indigenous fungi. The finding has significant implications for human disease, as scientists at the Cedars-Sinai Medical Genetics Institute found a variant of the gene for Dectin-1 that is strongly associated with severe forms of ulcerative colitis.

Photos: Images courtesy of Iliyan Iliev