title: The regulation of focal adhesion complex formation and salivary gland epithelial cell organization by nanofibrous PLGA scaffolds.
abstract: Nanofiber scaffolds have been useful for engineering tissues derived from mesenchymal cells, but few studies have investigated their applicability for epithelial cell-derived tissues. In this study, we generated nanofiber (250 nm) or microfiber (1200 nm) scaffolds via electrospinning from the polymer, poly-l-lactic-co-glycolic acid (PLGA). Cell-scaffold contacts were visualized using fluorescent immunocytochemistry and laser scanning confocal microscopy. Focal adhesion (FA) proteins, such as phosphorylated FAK (Tyr397), paxillin (Tyr118), talin and vinculin were localized to FA complexes in adult cells grown on planar surfaces but were reduced and diffusely localized in cells grown on nanofiber surfaces, similar to the pattern observed in adult mouse salivary gland tissues. Significant differences in epithelial cell morphology and cell clustering were also observed and quantified, using image segmentation and computational cell-graph analyses. No statistically significant differences in scaffold stiffness between planar PLGA film controls compared to nanofibers scaffolds were detected using nanoindentation with atomic force microscopy, indicating that scaffold topography rather than mechanical properties accounts for changes in cell attachments and cell structure. Finally, PLGA nanofiber scaffolds could support the spontaneous self-organization and branching of dissociated embryonic salivary gland cells. Nanofiber scaffolds may therefore have applicability in the future for engineering an artificial salivary gland.
authors.affiliation: Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Ave, LSRB 1086, Albany, NY 12222, USA.
authors.forename: Sharon J
authors.initials: SJ
authors.lastname: Sequeira
authors.forename: David A
authors.initials: DA
authors.lastname: Soscia
authors.forename: Basak
authors.initials: B
authors.lastname: Oztan
authors.forename: Aaron P
authors.initials: AP
authors.lastname: Mosier
authors.forename: Riffard
authors.initials: R
authors.lastname: Jean-Gilles
authors.forename: Anand
authors.initials: A
authors.lastname: Gadre
authors.forename: Nathaniel C
authors.initials: NC
authors.lastname: Cady
authors.forename: Bülent
authors.initials: B
authors.lastname: Yener
authors.forename: James
authors.initials: J
authors.lastname: Castracane
authors.forename: Melinda
authors.initials: M
authors.lastname: Larsen
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D002470:Cell Survival; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology* / Q000502:physiology*; D022001:Focal Adhesions / Q000502:physiology*; D019344:Lactic Acid / Q000737:chemistry*; D051379:Mice; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D012469:Salivary Glands / Q000166:cytology* / Q000502:physiology; D023822:Tissue Engineering / Q000295:instrumentation*; D054457:Tissue Scaffolds
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid