Fig. 1.

a–c Effects of trypsinization on cell spreading and migration of HUVECs. After trypsinization with 0.25 % trypsin–EDTA for 2, 3, and 4 min, respectively, the cells were subject to percentage-based (a) or spread area-based (b) cell spreading assay and migration assay (c). d, e Effects of cell passaging on cell spreading of HUVECs by measuring percentage of spread cells (d) or spread areas of individual cells (e). Values are expressed as mean ± SEM (A, n ≥ 18; B, n ≥ 470; C, n ≥ 6; D, n ≥ 27; E, n ≥ 400; all from three independent experiments; asterisk, P < 0.05)