Marked reduction in the numbers of absorptive enterocytes and goblet cells in Shp2 CKO mice.

A: Frozen sections of the ileum from control or Shp2 CKO mice at 3 to 4 weeks of age were immunostained with an antibody to β-catenin (green) and also stained with DAPI (blue). Representative images are shown in the left panel. Arrowheads indicate β-catenin–positive absorptive enterocytes. Scale bar, 100 μm. The number of β-catenin–positive absorptive enterocytes per villus was determined for the ileum (right panel). Data are means ± SE for 38 (control) or 32 (Shp2 CKO) villi from a total of three mice per group. ***P<0.0001 (Welch's t test). B: Frozen sections of the ileum and colon from control or Shp2 CKO mice at 3 weeks of age were immunostained with antibodies to mucin 2 (red) and to β-catenin (green). Representative images are shown in the left panel. Scale bar, 100 μm. The number of mucin 2 (Muc2)–positive goblet cells per villus was determined for the ileum (right panel). Data are means ± SE for 100 (control) or 93 (Shp2 CKO) villi from a total of three mice per group. ***P<0.0001 (Welch's t test). C: Frozen sections of the ileum from control or Shp2 CKO mice at 3 weeks of age were subjected to immunostaining with antibodies to lysozyme (red) and to β-catenin (green) as well as to staining of nuclei with DAPI (blue). Representative images are shown in the left panel. Scale bar, 50 μm. The number of lysozyme-positive Paneth cells per crypt was determined (right panel). Data are means ± SE for 150 crypts from a total of three mice per group. **P<0.01 (Student's t test). D: Paraffin sections of the ileum from control or Shp2 CKO mice at 3 to 4 weeks of age were subjected to in situ hybridization analysis of Olfm4 mRNA. Representative images are shown in the left panel. Scale bar, 50 μm. The number of Olfm4 mRNA–positive cells per crypt was determined (right panel). Data are means ± SE for 60 crypts from a total of two mice per group. N.S., not significant (Student's t test).