Matrix Stiffness Essential to Stem Cell Differentiation (3 of 3) (image) University of California - San Diego Share Print E-Mail Caption Cells grown on three hydrogels of the same stiffness all display fat cell markers and deform the underlying matrix material in the same way. Credit Adam Engler/UC San Diego Jacobs School of Engineering Usage Restrictions Embargoed until Aug. 10, 2014 at 1300 EST. 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.