IL‑15R‑alpha Deficiency Increases Mitochondrial Content (IMAGE) University of Pennsylvania School of Medicine Caption Muscles from mice lacking IL‑15R‑alpha and control mice were processed for presence of a mitochondrial marker. The mice lacking IL‑15R‑alpha show a greater number of darkly stained muscle fibers (right), indicating an increase in their mitochondrial content caused by reprogramming due to the lack of IL‑15R‑alpha. Credit Emidio E. Pistilli, PhD, & Tejvir S. Khurana, MD, PhD, Perelman School of Medicine, University of Pennsylvania. Image is based on a Figure from Pistilli et al. 2011. <i>Journal of Clinical Investigation</i>. Usage Restrictions None 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.