FIG. 4.
(A) Morphology of the HDMEC cultured on PC collagen constructs after 3 weeks in culture. Endothelial cells adhere to the PC collagen and retain characteristic cobblestone morphology with expression of endothelial cell marker PECAM-1 between cell–cell contacts (nuclei counterstained with 4′,6-diamidino-2-phenylindole [DAPI]). (B) SEM imaging of HDMEC on the PC constructs showed cells (arrows) adherent to the fibrillar collagen surface. (C) Histological examination of the PC constructs revealed a monolayer of adherent endothelial cells. (D, E) HDMEC stained positively for expression of basement membrane proteins laminin (D) and collagen type IV (E). Arrows indicate endothelial cells on the images.