FIGURE 4.

Surface topography modulates the maturity and position of focal adhesions. (A) Rat tenocytes cultured on a flat surface and the tendon imprint for 2, 4, 12, and 24 h, and stained for vinculin (fair gray color) and pointed with red arrows. Scale bars represent 20 µM. (B) Quantification of focal adhesion length indicates that on a flat surface, as the cells become larger, focal adhesions become longer indicating their maturation. Tenocytes on the tendon imprint, focal adhesion length is significantly smaller compared to the flat surface at the all-time point. (C) hMSCs cultured on a flat surface and a Topo1018 surface for 30 min, 2, 4, 12, and 24 h, and stained with vinculin (fair gray color) and pointed with red arrows. Scale bars represent 20 µM. (D) Focal adhesion length increases steadily in cells cultured on a flat surface. On the Topo1018 surface, we did not observe focal adhesions after 30 min and 2 h, and from 4 h onward, their length remained at similar levels and significantly shorter compared to their flat surface counterparts. (Error bars represent 95% confidence intervals, ****p < 0.001) (*’s correspond to comparisons between different culture substrates in the same time point). For all experiments, N = 3. (FA = focal adhesion).