LTB4 Model (IMAGE) University of California - San Diego Caption In obesity, extra fat triggers inflammation by releasing LTB4, which binds to receptors on nearby macrophages and activates them. Credit UC San Diego School of Medicine Usage Restrictions Use photo credit as indicated. License Licensed 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.