Biophysical Society Thematic Meeting| Aussois 2019

Biology and Physics Confront Cell-Cell Adhesion

Poster Abstracts

17-POS Board 17 EFFECT OF ADHERENS JUNCTIONS ON MECHANICAL PROPERTIES OF HUMAN MAMMARY EPITHELIAL CELLS. Hyunsu Lee 1 ; Martin Guthold 1 ; Keith Bonin 1 ; 1 Wake Forest University, Physics, Winston Salem, NC, USA Epithelial cells form a protective layer lining the outer surface of organs and tissues. Mammary epithelial cells form as single layers to provide the main structural component of mammary ducts. The mechanical properties of these epithelial cells are critical in tissue development and in maintaining mechanical homeostasis. The cytoskeleton of cells plays an important role in determining the mechanical properties of cells. In addition, intercellular adherens junctions – connections between the cytoskeletons of different cells – may also have a strong influence on the mechanical properties of cells in an epithelium. We used atomic force microscopy indentation to investigate the mechanical properties of human mammary epithelial cells (HMECs) in different states, ranging from isolated cells to confluent, highly polarized cells. Our results show that the stiffness of polarized cells in a monolayer increases fivefold, compared to single cells and unpolarized, confluent cells. Furthermore, we found that the stiffness of the polarized cells decreases to the level of single cells when adherens junctions are interrupted by removing free calcium ions with EDTA. Our data suggest that intercellular connections of actin fibers through adherens junctions are a primary contributor to the stiffness of cells in an epithelium.

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