title: In vitro and in vivo chitosan membranes testing for peripheral nerve reconstruction.
abstract: Tissue regeneration over a large defect with a subsequent satisfactory functional recovery still stands as a major problem in areas such as nerve regeneration or bone healing. The routine technique for the reconstruction of a nerve gap is the use of autologous nerve grafting, but still with severe complications. Over the last decades several attempts have been made to overcome this problem by using biomaterials as scaffolds for guided tissue regeneration. Despite the wide range of biomaterials available, functional recovery after a serious nerve injury is still far from acceptable. Prior to the use of a new biomaterial on healing tissues, an evaluation of the host's inflammatory response is mandatory. In this study, three chitosan membranes were tested in vitro and in vivo for later use as nerve guides for the reconstruction of peripheral nerves submitted to axonotmesis or neurotmesis lesions. Chitosan membranes, with different compositions, were tested in vitro, with a nerve growth factor cellular producing system, N1E-115 cell line, cultured over each of the three membranes and differentiated for 48h in the presence of 1.5% of DMSO. The intracellular calcium concentrations of the non-differentiated and of the 48h-differentiated cells cultured on the three types of the chitosan membranes were measured to determine the cell culture viability. In vivo, the chitosan membranes were implanted subcutaneously in a rat model, and histological evaluations were performed from material retrieved on weeks 1, 2, 4 and 8 after implantation. The three types of chitosan membranes were a viable substrate for the N1E-115 cell multiplication, survival and differentiation. Furthermore, the in vivo studies suggested that these chitosan membranes are promising candidates as a supporting material for tissue engineering applications on the peripheral nerve, possibly owing to their porous structure, their chemical modifications and high affinity to cellular systems.
authors.affiliation: Centro de Estudos de Ciência Animal, Instituto de Ciências e Tecnologias Agrárias e Agro-Alimentares, Universidade do Porto, Portugal.
authors.forename: M J
authors.initials: MJ
authors.lastname: Simões
authors.forename: A
authors.initials: A
authors.lastname: Gärtner
authors.forename: Y
authors.initials: Y
authors.lastname: Shirosaki
authors.forename: R M
authors.initials: RM
authors.lastname: Gil da Costa
authors.forename: P P
authors.initials: PP
authors.lastname: Cortez
authors.forename: F
authors.initials: F
authors.lastname: Gartnër
authors.forename: J D
authors.initials: JD
authors.lastname: Santos
authors.forename: M A
authors.initials: MA
authors.lastname: Lopes
authors.forename: S
authors.initials: S
authors.lastname: Geuna
authors.forename: A S P
authors.initials: AS
authors.lastname: Varejão
authors.forename: A Colette
authors.initials: AC
authors.lastname: Maurício
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002478:Cells, Cultured; D048271:Chitosan; D005260:Female; D048091:Guided Tissue Regeneration; D008567:Membranes, Artificial; D009416:Nerve Regeneration; D019635:Neurosurgical Procedures / Q000379:methods*; D010525:Peripheral Nerves / Q000601:surgery*; D051381:Rats; D017208:Rats, Wistar; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D008567:Membranes, Artificial; D048271:Chitosan