title: Nano-Biomechanical Study of Spatio-Temporal Cytoskeleton Rearrangements that Determine Subcellular Mechanical Properties and Endothelial Permeability.
abstract: The endothelial cell (EC) lining of the pulmonary vascular system forms a semipermeable barrier between blood and the interstitium and regulates various critical biochemical functions. Collectively, it represents a prototypical biomechanical system, where the complex hierarchical architecture, from the molecular scale to the cellular and tissue level, has an intimate and intricate relationship with its biological functions. We investigated the mechanical properties of human pulmonary artery endothelial cells (ECs) using atomic force microscopy (AFM). Concurrently, the wider distribution and finer details of the cytoskeletal nano-structure were examined using fluorescence microscopy (FM) and scanning transmission electron microscopy (STEM), respectively. These correlative measurements were conducted in response to the EC barrier-disrupting agent, thrombin, and barrier-enhancing agent, sphingosine 1-phosphate (S1P). Our new findings and analysis directly link the spatio-temporal complexities of cell re-modeling and cytoskeletal mechanical properties alteration. This work provides novel insights into the biomechanical function of the endothelial barrier and suggests similar opportunities for understanding the form-function relationship in other biomechanical subsystems.
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, USA. 60208.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, USA. 60208.
authors.forename: Reiner
authors.initials: R
authors.lastname: Bleher
authors.affiliation: Department of Medicine, University of Illinois, Chicago, IL, USA. 60612.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Brown
authors.affiliation: Arizona Health Sciences Center, The University of Arizona, Tucson, AZ, USA. 210202.
authors.forename: Joe G N
authors.initials: JG
authors.lastname: Garcia
authors.affiliation: Department of Medicine, University of Illinois, Chicago, IL, USA. 60612.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Dudek
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, USA. 60208.
authors.forename: Gajendra S
authors.initials: GS
authors.lastname: Shekhawat
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, USA. 60208.
authors.forename: Vinayak P
authors.initials: VP
authors.lastname: Dravid
mesh_terms: D001696:Biomechanical Phenomena; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000378:metabolism*; D042783:Endothelial Cells / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D055595:Mechanical Phenomena; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D036103:Nanotechnology; D010539:Permeability