Fig. 2. Loss of Apc along the crypt-villus axis induces progressive crypt extension associated with intense proliferation. (A) Representative Hematoxylin and Eosin (H&E)-stained sections of jejunum from control (left) and mutant mice (right) at day 4, shown at low and high magnification. (B) Representative H&E-stained sections of proximal colon from mutant mice (day 4), shown at low, medium and high magnification. Line indicates the junction between dysplastic (top section) and normal areas (bottom section). Arrows and arrowheads indicate mitotic and apoptotic cells, respectively. (C) Representative H&E- (top) and Ki-67- (bottom) stained sections of jejunum from control (day 4, D4) and mutant (D2, D3, D4) mice. Abnormal crypt extension and similar Ki67 staining were observed all along the small intestine from the duodenum to the ileum in the mutant mice. Brackets indicate the dysplastic zone.