title: Fiber alignment directs cell motility over chemotactic gradients.
abstract: The ability of tissue engineered scaffolds to direct cell behavior is paramount for scaffold design. Cell migration can be directed by various methods including chemical, adhesive, mechanical, and topographical cues. Electrospinning has emerged as a popular method to control topography and create fibrous scaffolds similar to that found in extracellular matrix. One major hurdle is limited cell infiltration and several studies have explored methods to alter electrospun materials to increase scaffold porosity; however, uniform cell distributions within scaffolds is still limited. Towards this, we investigated the motility of HUVECs on a model system of electrospun hyaluronic acid fibers under a gradient of VEGF and found that topographical cues dominate cell motility direction. Using time-lapse microscopy, cell aspect ratio, and migration angle were measured; cells were directed in a chemical gradient and/or on aligned electrospun fibers. Measurements of the persistence time demonstrated an additive effect of the chemical gradient and fiber alignment. However, when fibers were aligned perpendicular to a chemical gradient, cells were directed by fiber alignment and there was no effect of the chemical gradient. These results suggest that topographical cues may be more influential than chemical cues in directing cell motility and should be considered in material design.
authors.affiliation: Department of Biomedical Engineering, Wayne State University, 5050 Anthony Wayne Dr #2150, Detroit, MI 48201. hsundara@wayne.edu
authors.forename: Harini G
authors.initials: HG
authors.lastname: Sundararaghavan
authors.forename: Randi L
authors.initials: RL
authors.lastname: Saunders
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Hammer
authors.forename: Jason A
authors.initials: JA
authors.lastname: Burdick
mesh_terms: D002478:Cells, Cultured; D002633:Chemotaxis; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D044085:Microfluidics; D042461:Vascular Endothelial Growth Factor A / Q000008:administration & dosage
chemical_list: D042461:Vascular Endothelial Growth Factor A