Lung Organoids (IMAGE) University of Pennsylvania School of Medicine Caption Mouse (left) and human (right) alveolar progenitor cells grow into large lung organoids in culture, and make multiple types of epithelial cells including gas exchange type 1 cells (red) and surfactant-producing type 2 cells (green). Credit The lab of Ed Morrisey, Perelman School of Medicine, University of Pennsylvania. 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.