Cellular and Molecular Bioengineering

, Volume 4, Issue 1, pp 9–27 | Cite as

Effects of Morphology vs. Cell–Cell Interactions on Endothelial Cell Stiffness

  • Kimberly M. Stroka
  • Helim Aranda-EspinozaEmail author


Biological processes such as atherogenesis, wound healing, cancer cell metastasis, and immune cell transmigration rely on a delicate balance between cell–cell and cell–substrate adhesion. Cell mechanics have been shown to depend on substrate factors such as stiffness and ligand presentation, while the effects of cell–cell interactions on the mechanical properties of cells has received little attention. Here, we use atomic force microscopy to measure the Young’s modulus of live human umbilical vein endothelial cells (HUVECs). In varying the degree of cell–cell contact in HUVECs (single cells, groups, and monolayers), we observe that increased cell stiffness correlates with an increase in cell area. Further, we observe that HUVECs stiffen as they spread onto a glass substrate. When we weaken cell–cell junctions (i.e., through a low dose of cytochalasin B or treatment with a VE-cadherin antibody), we observe that cell–substrate adhesion increases, as measured by focal adhesion size and density, and the stiffness of cells within the monolayer approaches that of single cells. Our results suggest that while morphology can roughly be used to predict cell stiffness, cell–cell interactions may play a significant role in determining the mechanical properties of individual cells in tissues by careful maintenance of cell tension homeostasis.


Cell mechanics Cell spreading Focal adhesions Cell tension Actin 



This work was completed under an NSF Graduate Research Fellowship to KMS, NIH NRSA fellowship to KMS (NINDS Award Number F31NS068028) and NSF Award CMMI-0643783 to HAE. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Neurological Disorders and Stroke or the National Institutes of Health.


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© Biomedical Engineering Society 2010

Authors and Affiliations

  1. 1.Fischell Department of BioengineeringUniversity of Maryland, College ParkCollege ParkUSA

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