Myofibroblasts (image) University of California - San Diego Share Print E-Mail Caption Mouse colorectal tumors display inflammatory infiltration by macrophages (green) and activated stromal cells (red). The question of why and how tumors recruit immune cells remains unknown. Credit UC San Diego School of Medicine Usage Restrictions None Share Print E-Mail 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.