Figure 4.

Morphological response of single HUVECs under a constant shear stress of 20 dyne/cm². (a&b) Immunostaining (a) and scanning electron microscopy (b) images of HUVECs after the 6-hr shearing stimulation. The direction of the shear flow was from left to right, as indicated. Left: cells on the flat PDMS surface, right: cells on the PDMS micropost array. In a, HUVECs were stained for the nucleus (blue) and actin microfilaments (green), and the PDMS microposts were stained with DiI (red). Scale bars, 20 µm (a) and 10 µm (b). (c) Temporal evolutions of the shape directionality (left) and normalized cell area (right) of individual HUVECs during the time course of the 6-hr stimulation with the shear stress of 20 dyne/cm². The cell areas of single HUVECs were normalized to their baseline values measured right before the onset of the flow stimulation. Data represents the means ± SE (standard error) from 3 indepdent experiments, and cell number n = 20.