Traction Forces of Endothelial Cells under Slow Shear Flow.
Endothelial cells are constantly exposed to fluid shear stresses that regulate vascular morphogenesis, homeostasis, and disease. The mechanical responses of endothelial cells to relatively high shear flow such as that characteristic of arterial circulation has been extensively studied. Much less is known about the responses of endothelial cells to slow shear flow such as that characteristic of venous circulation, early angiogenesis, atherosclerosis, intracranial aneurysm, or interstitial flow. Here we used a novel, to our knowledge, microfluidic technique to measure traction forces exerted by confluent vascular endothelial cell monolayers under slow shear flow. We found that cells respond to flow with rapid and pronounced increases in traction forces and cell-cell stresses. These responses are reversible in time and do not involve reorientation of the cell body. Traction maps reveal that local cell responses to slow shear flow are highly heterogeneous in magnitude and sign. Our findings unveil a low-flow regime in which endothelial cell mechanics is acutely responsive to shear stress.
Institute for In Silico Medicine, University of Sheffield, Sheffield, United Kingdom; Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom; Institute for Bioengineering of Catalonia, Barcelona, Spain. Electronic address: c.perrault@sheffield.ac.uk.
Cecile M
CM
Perrault
Institute for Bioengineering of Catalonia, Barcelona, Spain.
Agusti
A
Brugues
Institute for Bioengineering of Catalonia, Barcelona, Spain.
Elsa
E
Bazellieres
Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom.
Pierre
P
Ricco
Institute for In Silico Medicine, University of Sheffield, Sheffield, United Kingdom; Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom; Institute for Bioengineering of Catalonia, Barcelona, Spain.
Damien
D
Lacroix
Institute for Bioengineering of Catalonia, Barcelona, Spain; Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain.
Xavier
X
Trepat
D000222:Adaptation, Physiological / Q000502:physiology; D001775:Blood Circulation / Q000502:physiology*; D002448:Cell Adhesion; D002450:Cell Communication; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000502:physiology*; D004867:Equipment Design; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000379:methods; D008853:Microscopy / Q000379:methods; D008955:Models, Cardiovascular; D013312:Stress, Physiological / Q000502:physiology*; D014471:Umbilical Veins