title: Control of cell migration direction by inducing cell shape asymmetry with patterned topography.
abstract: In this study, we explored the concept of introducing asymmetry to cell shapes by patterned cell culture substrates, and investigated the consequence of this induced asymmetry to cell migration behaviors. Three patterns, named "Squares", "Grating", and "Arcs" were fabricated, representing different levels of rotational asymmetry. Using time-lapse imaging, we systematically compared the motility and directionality of mouse osteoblastic cells MC3T3-E1 cultured on these patterns. Cells were found to move progressively faster on "Arcs" than on "Grating", and cells on "Squares" were the slowest, suggesting that cell motility correlates with the level of rotational asymmetry of the repeating units of the pattern. Among these three patterns, on the "Arcs" pattern, the least symmetrical one, cells not only moved with the highest velocity but also the strongest directional persistence. Although this enhanced motility was not associated with the detected number of focal adhesion sites in the cells, the pattern asymmetry was reflected in the asymmetrical cell spreading. Cells on the "Arcs" pattern consistently displayed larger cytoplasmic protrusion on one side of the cell. This asymmetry in cell shape determined the direction and speed of cell migration. These observations suggest that topographical patterns that enhance the imbalance between the leading and trailing fronts of adherent cells will increase cell speed and control movement directions. Our discovery shows that complex cell behaviors such as the direction of cell movement are influenced by simple geometrical principles, which can be utilized as the design foundation for platforms that guide and sort cultured cells.
authors.affiliation: Department of Electronic Engineering, City University of Hong Kong, Hong Kong.|Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.
authors.forename: Q Y
authors.initials: QY
authors.lastname: Tang
authors.affiliation: Department of Electronic Engineering, City University of Hong Kong, Hong Kong.|Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.|School of Electronic and Optical Engineering, Nanjing University of Science and Technology, China.
authors.forename: W X
authors.initials: WX
authors.lastname: Qian
authors.affiliation: Department of Electronic Engineering, City University of Hong Kong, Hong Kong.|Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.
authors.forename: Y H
authors.initials: YH
authors.lastname: Xu
authors.affiliation: Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.|Department of Biology and Chemistry, City University of Hong Kong, Hong Kong.
authors.forename: S
authors.initials: S
authors.lastname: Gopalakrishnan
authors.affiliation: Department of Electronic Engineering, City University of Hong Kong, Hong Kong.|Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.|College of Electronic Science and Technology, Dalian University of Technology, China.
authors.forename: J Q
authors.initials: JQ
authors.lastname: Wang
authors.affiliation: Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.|Department of Biology and Chemistry, City University of Hong Kong, Hong Kong.
authors.forename: Y W
authors.initials: YW
authors.lastname: Lam
authors.affiliation: Department of Electronic Engineering, City University of Hong Kong, Hong Kong.|Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.
authors.forename: S W
authors.initials: SW
authors.lastname: Pang
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002465:Cell Movement; D048430:Cell Shape; D051379:Mice
keywords: cell migration direction; directional persistence; imbalance leading and trailing fronts; patterned topography; rotational symmetry of patterns