Bacterial control in the intestines (IMAGE) University of Pennsylvania Caption Researchers from Penn observed, for the first time, an intestinal pyogranuloma, formed in response to Yersinia infection. The organized grouping of cells includes monocytes (in green), neutrophils (in magenta), and Yersinia bacteria (in white), and depends on monocytes to form and to control infection, the team found. Credit Courtesy of Brodsky Laboratory Usage Restrictions in context of reporting License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.