Morphologic changes of HUVECs induced by prolonged KLF2 overexpression. HUVECs were transduced with Lenti-mock (A,C,E,G) or Lenti-KLF2 (B,D,F,H) and analyzed 7 days after transduction. (A-B) Immunofluorescence using an anti–human KLF2 antibody. (C-D) Phase-contrast imaging. (E-F) Phalloidin-TRITC staining for F-actin stress fibers. (G-H) Close-ups of phalloidin-FITC staining (green) with VWF immunofluorescence (red) used for orientation. Images were acquired using a 20 × /0.5 NA objective (A-F) or a 63 × /1.4 NA oil objective (G-H).