Unique Basal Progenitor Cells (IMAGE) Columbia University Irving Medical Center Caption Arrows point to a population of unique basal progenitor cells (p63+ KRT7+ Claudin18-) located at the equivalent of the gastroesophageal junction in a mouse model. Credit Lab of Jianwen Que, MD, PhD, Columbia University Medical Center Usage Restrictions with credit 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.