Fig. 3. Spreading of human gastric epithelial cells is stimulated by H. pylori by induction of MMP-7. (A–C) Frames taken at 17, 32 and 52 hours from the same human gastric gland (control subject) during time-lapse video-microscopy. (D–F) Similar frames taken from a gland from a H. pylori-positive subject. Subsequent staining of cell nuclei with Hoechst 33342 revealed 86 cells in A–C and 88 cells in D F. (G) The area of gastric colonies expressed relative to cell numbers at 17 and 40 hours indicates increased migration in H. pylori-positive (n=8; mean data from 4–15 glands per subject) compared with control subjects (n=12; mean data of 4–15 glands per subject). (H) Pretreatment with antisense (AS) oligonucleotides to MMP-7 (2 µM) inhibited the spreading of gastric glands at 40 hours from H. pylori-positive subjects (n=7), but had only a slight effect on control glands (n=7). Data expressed as means±s.e.m. *P<0.05. In A–F: bar, 200 µm.