Figure 2.

Intestinal cell proliferation is inhibited in Dkk1 transgenic mice. Immunohistochemical analysis of small intestine sections from wild-type (A,C) or transgenic (B,D) adult mice stained with an antibody against proliferating cell antigen Ki-67, and wild-type (E) or transgenic (F) adult mice labeled with BrdU and stained with an anti-BrdU antibody. Note that proliferative cells are abundantly present in regularly distributed crypts flanking the villi from the wild-type intestine (C, inset), but are absent from patchy cryptless areas in the transgenic intestine, persisting only in scarce residual crypts (D, inset). Original magnification: A,B, 2×; C,D, 10×; insets, 60×; E,F, 20×.