Fig. 5. Interstitial flow effects are mediated through ₁ß₁ integrins. (A) Confocal images of cells under normal, ₁ß₁- and ₂ß₁-neutralized flow conditions for 2 days (green, f-actin; red, -SMA; arrow indicates flow direction). (B) Bar graphs indicating -SMA expression levels for the respective normal and bioneutralized conditions (**P<0.01 using Dunn's test); box plot shows 95% confidence intervals with midline showing the median. (C,D) Effects of integrin blocking on cell spreading and density (**P<0.01 using Dunnett's test). (E,F) Effects of integrin blocking on the alignment and orientation of cell and collagen fibers under the various experimental conditions (*P<0.05; **P<0.01 using Dunnett's test). Error bars indicate s.d. (G) Contraction of free-floating gels by fibroblasts after no treatment (control) or treatment with either of the integrin-blocking antibodies as indicated; only neutralizing ₂ß₁ integrin prevents contraction. Bar, 200 µm.