Figure 2.

Sonic hedgehog (Shh) protein expression along the human and murine gastrointestinal tract. (A–G) Sections of the human gastrointestinal tract; immunohistochemical staining with an antibody against the Shh precursor protein. We found intense staining in the fundic glands (B) whereas no staining was found in the oesophagus (A), antrum (C), Brunner’s glands (D), duodenum (E), ileum (F), or colon (G). Sections of the murine gastrointestinal tract (H–N) gave the same results. Shown are: forestomach (H), fundic glands (I), antral glands (J), duodenum (K), jejunum (L), ileum (M), and colon (N). Control experiments in three adjacent sections are also shown (O–Q). No signal was found in the human fundic gland with isotype control antibody (O) and the signal detected with the anti-Shh antibody (P) was efficiently blocked with a blocking peptide (Q).