Gut microbe link to bowel disease

A new study has zeroed in on the gut microbiota of patients lacking the most abundant antibody in the human body — immunoglobulin A (or IgA) — which helps explain why some people may be particularly susceptible to inflammatory bowel disease. The results, published in Science , add to a growing body of work detailing how the gut microbiome (or the complex community of microorganisms in the digestive tract) play a critical role in various aspects of human health. Many of the interactions in the microbiome are mediated by IgA, and as many as 1 in 500 Caucasian people are deficient in the antibody. These individuals often exhibit mild versions of complications including autoimmunity, respiratory infections and intestinal disorders. Scientists suspect that IgA regulates the relationship between microbiota and the immune system by attaching to bacteria, but its exact impact on the microbiome remains poorly understood.