"Shift" cell Reticulocytes
The larger, grey-pink erythrocyte in the center of this field is called a polychromatophilic or "shift" cell. It has newly entered the blood, and is thought to indicate erythropoieitin stimulation of erythropoiesis. Reticulocytes. The dark purple reticulin in red blood cells newly entering the blood is demonstrated by this new methylene blue stain.