Micro Pyramids (image) Harvard John A. Paulson School of Engineering and Applied Sciences Share Print E-Mail Caption This is a scanning-electron microscope image of chemically-fixed HeLa cancer cells on the substrate. The tips of the pyramids create tiny holes in the cell membranes, allowing molecular cargo to diffuse into the cells. Credit (Image courtesy of Harvard SEAS) Usage Restrictions with credit 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.