title: Fabrication and characterization of biomimetic multichanneled crosslinked-urethane-doped polyester tissue engineered nerve guides.
abstract: Biomimetic scaffolds that replicate the native architecture and mechanical properties of target tissues have been recently shown to be a very promising strategy to guide cellular growth and facilitate tissue regeneration. In this study, porous, soft, and elastic crosslinked urethane-doped polyester (CUPE) tissue engineered nerve guides were fabricated with multiple longitudinally oriented channels and an external non-porous sheath to mimic the native endoneurial microtubular and epineurium structure, respectively. The fabrication technique described herein is highly adaptable and allows for fine control over the resulting nerve guide architecture in terms of channel number, channel diameter, porosity, and mechanical properties. Biomimetic multichanneled CUPE guides were fabricated with various channel numbers and displayed an ultimate peak stress of 1.38 ± 0.22 MPa with a corresponding elongation at break of 122.76 ± 42.17%, which were comparable to that of native nerve tissue. The CUPE nerve guides were also evaluated in vivo for the repair of a 1 cm rat sciatic nerve defect. Although histological evaluations revealed collapse of the inner structure from CUPE TENGs, the CUPE nerve guides displayed fiber populations and densities comparable with nerve autograft controls after 8 weeks of implantation. These studies are the first report of a CUPE-based biomimetic multichanneled nerve guide and warrant future studies towards optimization of the channel geometry for use in neural tissue engineering.
authors.affiliation: Department of Bioengineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802.
authors.forename: Richard T
authors.initials: RT
authors.lastname: Tran
authors.forename: Wai Man
authors.initials: WM
authors.lastname: Choy
authors.forename: Hung
authors.initials: H
authors.lastname: Cao
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Qattan
authors.forename: Jung-Chih
authors.initials: JC
authors.lastname: Chiao
authors.forename: Wing Yuk
authors.initials: WY
authors.lastname: Ip
authors.forename: Kelvin Wai Kwok
authors.initials: KW
authors.lastname: Yeung
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
mesh_terms: D000818:Animals; D040761:Biomimetic Materials / Q000494:pharmacology*; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004548:Elasticity / Q000187:drug effects; D048091:Guided Tissue Regeneration; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology; D011091:Polyesters / Q000494:pharmacology*; D016062:Porosity; D011917:Rats, Inbred Lew; D012584:Sciatic Nerve / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D023822:Tissue Engineering / Q000379:methods*; D014025:Titanium / Q000494:pharmacology; D014520:Urethane / Q000494:pharmacology*
chemical_list: D003432:Cross-Linking Reagents; D011091:Polyesters; D014520:Urethane; D014025:Titanium
keywords: biodegradable elastomer; biomimetic; multichanneled scaffold; nerve guide; tissue engineering