Macrophage in a Pore (IMAGE) ETH Zurich Caption This is a macrophage in a pore measuring 20 micrometres across (electron microscope image). Credit ETH Zurich/Nikhil Jain and Isabel Gerber 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.