Modified Adeno-Associated Viruses Locked (image) Rice University Caption Modified adeno-associated viruses developed at Rice University are "locked" by peptides that respond to the presence of two proteases likely to be overexpressed at the site of cancerous or other diseased tissues. The proteases chew off the peptides, thereby unlocking the virus and allowing it to deliver its therapeutic cargo. Credit Junghae Suh/Rice University Usage Restrictions For news media reporting purposes only. 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.