title: Early responses of vascular endothelial cells to topographic cues.
abstract: Vascular endothelial cells in vivo are exposed to multiple biophysical cues provided by the basement membrane, a specialized extracellular matrix through which vascular endothelial cells are attached to the underlying stroma. The importance of biophysical cues has been widely reported, but the signaling pathways that mediate cellular recognition and response to these cues remain poorly understood. Anisotropic topographically patterned substrates with nano- through microscale feature dimensions were fabricated to investigate cellular responses to topographic cues. The present study focuses on early events following exposure of human umbilical vein endothelial cells (HUVECs) to these patterned substrates. In serum-free medium and on substrates without protein coating, HUVECs oriented parallel to the long axis of underlying ridges in as little as 30 min. Immunocytochemistry showed clear differences in the localization of the focal adhesion proteins Src, p130Cas, and focal adhesion kinase (FAK) in HUVECs cultured on topographically patterned surfaces and on planar surfaces, suggesting involvement of these proteins in mediating the response to topographic features. Knockdown experiments demonstrated that FAK was not necessary for HUVEC alignment in response to topographic cues, although FAK knockdown did modulate HUVEC migration. These data identify key events early in the cellular response to biophysical stimuli.
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California Davis, Davis, California, USA.
authors.forename: Britta
authors.initials: B
authors.lastname: Dreier
authors.forename: Joshua Z
authors.initials: JZ
authors.lastname: Gasiorowski
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Morgan
authors.forename: Paul F
authors.initials: PF
authors.lastname: Nealey
authors.forename: Paul
authors.initials: P
authors.lastname: Russell
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Murphy
mesh_terms: D001485:Basement Membrane / Q000378:metabolism*; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D050719:Crk-Associated Substrate Protein / Q000378:metabolism; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism*; D006801:Humans; D040542:Mechanotransduction, Cellular; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering; D015398:Signal Transduction
chemical_list: C493841:BCAR1 protein, human; D050719:Crk-Associated Substrate Protein; D034741:RNA, Small Interfering; D051416:Focal Adhesion Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src)
keywords: cell signaling; focal adhesion kinase; surface topography; vascular endothelial cells