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Mechanobiology of Disease
Poster Abstracts
103
12-POS
Board 12
Physical Characterization of Cellular Transition During Epithelial Monolayer Expansion
Youngbin Cho
1
, Bomi Gweon
2
, Jacob Notbohm
3
, Ung Hyun Ko
1
, Hwanseok Jang
4
, Yongdoo
Park
4
, Jennifer H. Shin
1
.
1
Korea Advanced Institute of Science and Technology, Daejeon, South Korea,
2
Hanyang
University, Seoul, South Korea,
3
Harvard University, Cambridge, MA, USA,
4
Korea University,
Seoul, South Korea.
During regeneration, metastasis, and morphogenesis, cells often migrate as a pack in a collective
manner in vivo. Within the cell monolayer, the cellular motion is regulated by the forces from
their surroundings through physical adhesions to the substrate and the neighboring cells. In
highly packed cells, a jammed state, cells show limited intercellular motion due to the stable cell-
cell junctions while the cells display relatively unrestrained motion in an unjammed state. When
the cells are patterned as a monolayer island, the monolayer expansion accompanies EMT-like
phenotypic cell transition, from the migrating edge. Such cellular transition involves dynamic
remodeling of physical junctions and stresses. Recent researchers have studied the key molecules
and mechanisms regulating the transition of cellular phenotypes but the dynamic correlation
between the key junction molecules and physical force redistribution are not fully understood
yet. Here, we aimed to understand the correlation between physical stresses and cellular
components. We visualized the physical force distribution within the patterned epithelial
monolayer using traction force microscopy (TFM) and monolayer stress microscopy (MSM).
Real-time force measurement by TFM and MSM revealed the two distinct groups of cells in the
monolayer; the 3-4 cell layers' width of the mesenchymal-like band around the monolayer edge
and epithelial-like region at the core. Cells in the mesenchymal band feature the developed
lamellipodia and high inward traction with fast migration while cells at the core maintain tight
cell-cell junctions with limited migration speed. Furthermore, our dynamic adhesion analysis
revealed the existence of an intermediate single-celled layer balancing between mesenchymal
band and epithelial region, with no biased physical polarity.