title: Effects of matrix composition, microstructure, and viscoelasticity on the behaviors of vocal fold fibroblasts cultured in three-dimensional hydrogel networks.
abstract: Vocal fold diseases and disorders are difficult to treat surgically or therapeutically. Tissue engineering offers an alternative strategy for the restoration of functional vocal folds. As a first step toward vocal fold tissue engineering, we investigated the responses of primary vocal fold fibroblasts (PVFFs) to two types of collagen and hyaluronic acid (HA)-based hydrogels that are compositionally similar, but structurally variable and mechanically different. Type A hydrogels were composed of mature collagen fibers reinforced by oxidized HA, whereas type B hydrogels contained immature collagen fibrils interpenetrated in an amorphous, covalently cross-linked HA matrix. PVFFs encapsulated in either matrix adopted a fibroblastic morphology and expressed genes related to important extracellular matrix proteins. DNA analysis indicated a linear growth profile for cells encapsulated in type B gels from day 0 to 21, in contrast to an initial dormant, nonproliferative period from day 0 to 3 experienced by cells in type A gels. At the end of the culture, similar DNA content was detected in both types of constructs. A reduction in collagen content was observed for both types of constructs after 28 days of culture, with type A constructs generally retaining higher amounts of collagen than type B constructs. The HA content in the constructs decreased steadily throughout the culture, with type A constructs consistently exhibiting less HA than type B constructs. Using the torsional wave analysis, we found that the elastic moduli for type A constructs decreased sharply during the first week of culture, followed by 2 weeks of matrix stabilization without significant changes in matrix stiffness. Conversely, the elastic modulus for type B constructs increased moderately over time. It is postulated that PVFFs residing in gels alter the matrix organization, chemical compositions, and viscoelasticity through cell-mediated remodeling processes.
authors.affiliation: Department of Materials Science and Engineering, University of Delaware , Newark, Delaware, USA.
authors.forename: Alexandra J E
authors.initials: AJ
authors.lastname: Farran
authors.forename: Sean S
authors.initials: SS
authors.lastname: Teller
authors.forename: Amit K
authors.initials: AK
authors.lastname: Jha
authors.forename: Tong
authors.initials: T
authors.lastname: Jiao
authors.forename: Rohan A
authors.initials: RA
authors.lastname: Hule
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Clifton
authors.forename: Darrin P
authors.initials: DP
authors.lastname: Pochan
authors.forename: Randall L
authors.initials: RL
authors.lastname: Duncan
authors.forename: Xinqiao
authors.initials: X
authors.lastname: Jia
mesh_terms: D000818:Animals; D001483:Base Sequence; D001672:Biocompatible Materials / Q000737:chemistry; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry; D017931:DNA Primers / Q000235:genetics; D055119:Elastic Modulus; D004548:Elasticity; D005109:Extracellular Matrix / Q000737:chemistry; D015870:Gene Expression; D006820:Hyaluronic Acid / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010641:Phenotype; D013314:Stress, Mechanical; D034421:Sus scrofa; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry; D014783:Viscosity; D014827:Vocal Cords / Q000166:cytology* / Q000502:physiology*
chemical_list: D001672:Biocompatible Materials; D017931:DNA Primers; D020100:Hydrogels; D006820:Hyaluronic Acid; D003094:Collagen