title: Hierarchically structured nerve guidance channels based on poly-3-hydroxybutyrate enhance oriented axonal outgrowth.
abstract: Traumatic peripheral nerve lesions can cause local anesthesia, paralysis and loss of autonomic control. Reconstruction using engineered nerve guidance conduits (NGCs) is rarely successful due to the sub-optimal characteristics of the conduits. To address the demands of clinical practice, we developed a hierarchically structured NGC from slowly resorbing poly(3-hydroxybutyric acid) (P3HB). The NGC consists of a permeable single-lumen tube and melt-spun fibrillar lumen fillers. Permeable tubes were constructed from P3HB/poly(ɛ-caprolactone) (PCL) blends or poly(3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P(3HB-co-4HB)). Polyvinylpyrrolidone was used as a porogen in solvent-free thermoplastic processing, followed by selective polymer leaching. All tested material compositions showed hydrolytic degradation after 16weeks in phosphate buffered saline, whereas P3HB/PCL tubes maintained mechanical strength compared to (P(3HB-co-4HB)). The porous scaffolds allowed diffusion of large molecules (∼70kDa). In vitro studies demonstrated that mouse fibroblasts survived and proliferated inside closed porous tubes. An in vitro model of axonal regeneration using dorsal root ganglia and sympathetic cervical ganglia demonstrated that the NGCs successfully supported neuron survival and neurite outgrowth. The introduction of fibrillar lumen fillers promoted oriented neurite growth and coating with extracellular matrix proteins further increased ganglia attachment and cell migration. In this study we show that P3HB-based NGCs scaffolds have potential in long gap peripheral nerve repair strategies.
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Institute of Material Science, Helmholtzstrasse 7, 01069 Dresden, Germany. Electronic address: hinueber@ipfdd.de.
authors.forename: C
authors.initials: C
authors.lastname: Hinüber
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Chwalek
authors.affiliation: Technische Universität Dresden, Institute of Anatomy/University Hospital Carl Gustav Carus, Fetscherstr. 74, 01307 Dresden, Germany.
authors.forename: F J
authors.initials: FJ
authors.lastname: Pan-Montojo
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Nitschke
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Vogel
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Brünig
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Institute of Material Science, Helmholtzstrasse 7, 01069 Dresden, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Heinrich
authors.affiliation: Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Center for Regenerative Therapies Dresden, Tatzberg 47, 01187 Dresden, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Werner
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects / Q000378:metabolism*; D002448:Cell Adhesion / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002645:Chickens; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects; D005728:Ganglia, Sympathetic / Q000166:cytology / Q000187:drug effects; D048091:Guided Tissue Regeneration; D006868:Hydrolysis / Q000187:drug effects; D006885:Hydroxybutyrates / Q000494:pharmacology*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D009416:Nerve Regeneration / Q000187:drug effects*; D010539:Permeability / Q000187:drug effects; D011091:Polyesters / Q000494:pharmacology*; D016062:Porosity / Q000187:drug effects; D000094122:Polyhydroxybutyrates
chemical_list: D006885:Hydroxybutyrates; D011091:Polyesters; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates
keywords: Nerve guide conduit; Nerve regeneration; Neural cell; Polyhydroxybutyric acid; Porosity