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Title: Migration and division in cell monolayers on substrates with topological defects
Collective movement and organization of cell monolayers are important for wound healing and tissue development. Recent experiments highlighted the importance of liquid crystal order within these layers, suggesting that +1 topological defects have a role in organizing tissue morphogenesis. We study fibroblast organization, motion, and proliferation on a substrate with micron-sized ridges that induce +1 and −1 topological defects using simulation and experiment. We model cells as self-propelled deformable ellipses that interact via a Gay–Berne potential. Unlike earlier work on other cell types, we see that density variation near defects is not explained by collective migration. We propose instead that fibroblasts have different division rates depending on their area and aspect ratio. This model captures key features of our previous experiments: the alignment quality worsens at high cell density and, at the center of the +1 defects, cells can adopt either highly anisotropic or primarily isotropic morphologies. Experiments performed with different ridge heights confirm a prediction of this model: Suppressing migration across ridges promotes higher cell density at the +1 defect. Our work enables a mechanism for tissue patterning using topological defects without relying on cell migration.  more » « less
Award ID(s):
1915491
PAR ID:
10565200
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
National Academy of Sciences USA
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
30
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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