P. Dieterich et al., Quantitative morphodynamics of endothelial cells within confluent culturesin response to fluid shear stress, BIOPHYS J, 79(3), 2000, pp. 1285-1297
To evaluate shear stress-induced effects on cultured cells we have extended
the mechanical setup of a multichannel in vitro rheological system and dev
eloped software allowing entire processing control and image data analysis.
The Values of cell motility, degree of orientation (alignment), and cell e
longation were correlated as a function of time (morphodynamics). Collectiv
e and individual endothelial cells within confluent cultures displayed a sh
ear stress-dependent characteristic phase behavior of the following time co
urse: resting conditions (phase I), change of motility (phase II), onset of
alignment (phase III), and finally cell elongation (phase IV). Especially
cell motility was characterized by a randomized zigzag movement around mean
trajectories (fluctuations) together with mean cell locomotion. Onset of s
hear stress caused a down-regulation of fluctuations of 30% within <10 min
and simultaneously increased locomotion velocities preferring the flow dire
ction (phase II). After a lag period of 10 to 20 min cells orientated in th
e direction of flow (phase III) without significant cell elongation, which
finally occurs within hours (phase IV). These data provide first evidence t
hat cells within confluent endothelial monolayers respond to shear stress w
ith a characteristic phase behavior.