Enrichment of human IgA-coated bacterial vesicles in ulcerative colitis as a driver of inflammation.

Summary: People with ulcerative colitis (UC) have long-lasting swelling and pain in their gut. Scientists wanted to know exactly how gut bacteria cause this problem. They looked at fluid from the colons of patients. They found that in UC patients, tiny bubbles made by bacteria (called vesicles) are covered in a special immune protein called IgA. These coated bubbles act like a spark, causing a strong and painful swelling reaction in the gut's immune cells.