Nanohydroxyapatite-Blasted Bioactive Surface Drives Shear-Stressed Endothelial Cell Growth and Angiogenesis

Figure 4

The angiogenic effect of HAnano® was measured by a wound healing assay. (a) Endothelial cell forming a confluent monolayer. (b) In vitro “wound” was created by a straight-line scratch across the endothelial cell monolayer (). At time 0 (), the endothelial cell were scratched and subjected to conditioned medium, respecting the culture groups, as follows: Ctrl: RPMI (c, g); shear stress: endothelial cell in shear stress model (d, h); shear stress W/DAE: shear-stressed endothelial cell subjected with Ti-enriched medium by DAE (w/DAE) (e,i); shear stress HAnano®: shear-stressed endothelial cell subjected with Ti-enriched medium by HAnano® (nano-HA) (f, j). The scratch wound assay was used to assess the migration capacity of the endothelial cells under different conditioned media. The wound area was estimated by calculating the cell-free area in captured images using the ImageJ software (NIH, Bethesda, MD). The migration rate is expressed in percentage as the change in the wound area over time, the scratch area at time point 0 hours was set to 100%, and the other ones are represented as wound closure expressed as the remaining area uncovered by the cells in percentage. (k) The statistically significant changes are represented by when compared with the Ctrl group, by ^@ when compared to the SS group, and by ^# when compared to the W/DAE SS group. Significant differences were considered when .