(IMAGE) Institute of Science and Technology Austria Caption While in the above picture immune cells (bright green) are able to invade the tissue of the fruit fly embryo on the central top side, they are less successful when their protective shell is weakened (picture below). Credit © Stephanie Wachner / IST Austria Usage Restrictions - License Original 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.