Momentum - The Magazine for Virginia Tech Mechanical Engineering Vol. 3 No. 3 Fall 2018 | Page 24

“Knowing this sensitivity to cylindrical platforms, we did a study [pub-
lished in Molecular Biology of the Cell] where we showed protrusion driv-
en cell invasion on fibers of varying diameters,” Nain said. “We suspended
fibers and put cells on either side. Based on both the separation distance
between the fibers and the diameter of fibers, the cells will come out singly,
or if the fibers are closer together, they will move as a stream (Figure 4).”
This behavior of invasion is similar to reported in vivo streaming of cells
from a tumor. Interestingly, single cells invaded by recoiling, similar to
release of a stretched rubber band. “Post invasion, we observed that depend-
ing upon the distance and orientation of fiber networks, migrating cells
from both sides approached each other and formed gaps that closed or did
not (Figure 5), thus providing a new method to study wound healing,” Nain
and Behkam said.
They identified a critical distance of ~375 microns beyond which there
was no gap closure. “There is more study to be done, but we now have a
way to engineer gaps based on the separation distance of the fibers. We
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FALL 2018
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Figure 5
Design of fiber networks to study closing and non-closing gaps in
wound healing.