Youngblood & Zebley of St. Jude (IMAGE) St. Jude Children's Research Hospital Caption Senior author Ben Youngblood, PhD, and co-author Caitlin Zebley, MD, both of Immunology at St. Jude, discover how T cells have a dual biological personality. Credit St. Jude Children's Research Hospital 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.