Persistence of hyperplastic islets lacking proliferating and apoptotic cells in some RIP7-rtTA × tet-Tag mice. Persistence of hyperplastic islets lacking proliferating and apoptotic cells in some RIP7-rtTA × tet-Tag mice. Mice treated with dox between 3 and 8 weeks of age were analyzed at 16 weeks of age. Pancreas sections were stained with HE (A), Tag antibody (B), and BrdU antibody (C) and were analyzed in a TUNEL assay (D). Magnification is 66×. Irina Berkovich, and Shimon Efrat Diabetes 2001;50:2260-2267 ©2001 by American Diabetes Association