HGF-Induced Cell Scatter - Cellular Potts Models: Multiscale Extensions and Biological Applications - page 24

FIGURE 2.6: HGF-mediated increase of motility: comparison of single-cell
motion tracks obtained by 24-h time-lapse video-recordings (A-B, see [101])
and 3000 MCS simulations (C-D) of ARO cells cultured in the absence (N.S.)
and in the presence of HGF, as indicated. In the experiments, the trajectories
are obtained by tracking continuously the motion of the nucleus of a cell, while
in the simulations, they are formed by the position of the center of mass of
the single cells at each time step. Experimentally, this would correspond to
track the position of the nucleus every 30 seconds (1 MCS is set equal to 30
s). Ten representative tracks were chosen for each case and optimally arrayed
for picture presentation. The oval positioned at the center of each group of
tracks represents the size of a single cell.
is wounded with a pipette tip and incubated for 24 h in the presence HGF;
see [101].
In the simulation shown in Figure 2.7, the culture is formed by two
masses of 120 virtual cells distributed over an area of about 700 m
700 m (350 350 lattice sites), while the other parameters are the same
as in the simulations of Fig 2.3. The gap is of about 120 m (60 lattice
sites): the maximum value, deduced from the above results, for which the two
colonies encounter within the time limit (24 h); for the full simulation refer
to calvino.polito.it/preziosi/AROsim2.avi. The time needed to invade the
space between the colonies, in the cases of T = 40 and T = 50, is evaluated
in Figure 2.8 as a function of dierent cell{cell adhesion parameter values.
For strong intercellular bonds, corresponding to J C;C < 30, ARO cells display
barely no detectable healing after 3000 MCS (i.e., nearly 24 h), which is in-
dicative of an inability to invade the tissue, while for an intermediate range
(corresponding to 30 < J C;C < 70) the time necessary to fill the gap decreases
until a sort of limit threshold characteristic of the process: about 800 MCS at
T = 40 and 600 MCS at T = 50.