The Bulge Stands Alone (IMAGE) Rockefeller University Caption Hair follicle stem cells lacking the protein FOXC1 can only retain one old bulge in their hair follicles, while normal stem cells can keep up to four. Credit The Laboratory of Mammalian Cell Biology and Development at Rockefeller University/PNAS Usage Restrictions Image may be used only to illustrate the research described in the accompanying release. 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.