Sterile cell scraper

hUCB-MSCs were cultured until 90% confluence in 35-mm dishes and scratched with a sterile cell scraper (Fisher Scientific, Pittsburgh, PA, USA). The border of the denuded area was marked with a fine line immediately, and the cells were incubated with 10 μM of AA in serum-free medium. Fetal bovine serum (2%) was treated for positive control. The cell migration was observed with microscope during incubation with a × 100 objective.

hAMSCs were grown to 50–60% confluence and then the plates were scratched with a sterile cell scraper (Fisher, Waltham, MA, USA; 08-773-2) to generate a 5-mm-wide area free of cells. The scratch border was marked with a fine line immediately after the scraping. The migration of cells was assessed as a function of how far from the scratch line the cells had migrated to the margin place over the course of 12 h. The cells were then fixed with 4% PFA and stained with DAPI (Invitrogen, D1306) for visualization of cell nuclei. The number of nuclei that had migrated over the scratch line was counted using the Image J program version 1.47 (NIH, Bethesda, MD, USA) (more than 12 random fields in each group were counted by blinded observers).