title: Mechanical fatigue performance of PCL-chondroprogenitor constructs after cell culture under bioreactor mechanical stimulus.
abstract: In tissue engineering of cartilage, polymeric scaffolds are implanted in the damaged tissue and subjected to repeated compression loading cycles. The possibility of failure due to mechanical fatigue has not been properly addressed in these scaffolds. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. This is related to inherent discontinuities in the material due to the micropore structure of the macro-pore walls that act as stress concentration points. In this work, chondrogenic precursor cells have been seeded in poly-ε-caprolactone (PCL) scaffolds with fibrin and some were submitted to free swelling culture and others to cyclic loading in a bioreactor. After cell culture, all the samples were analyzed for fatigue behavior under repeated loading-unloading cycles. Moreover, some components of the extracellular matrix (ECM) were identified. No differences were observed between samples undergoing free swelling or bioreactor loading conditions, neither respect to matrix components nor to mechanical performance to fatigue. The ECM did not achieve the desired preponderance of collagen type II over collagen type I which is considered the main characteristic of hyaline cartilage ECM. However, prediction in PCL with ECM constructs was possible up to 600 cycles, an enhanced performance when compared to previous works. PCL after cell culture presents an improved fatigue resistance, despite the fact that the measured elastic modulus at the first cycle was similar to PCL with poly(vinyl alcohol) samples. This finding suggests that fatigue analysis in tissue engineering constructs can provide additional information missed with traditional mechanical measurements.
authors.affiliation: Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.|Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.
authors.forename: Juan Alberto
authors.initials: JA
authors.lastname: Panadero
authors.affiliation: Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Vitor
authors.initials: V
authors.lastname: Sencadas
authors.affiliation: Departamento de Engenharia Biólogica, da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Sonia C M
authors.initials: SC
authors.lastname: Silva
authors.affiliation: Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Clarisse
authors.initials: C
authors.lastname: Ribeiro
authors.affiliation: Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Vitor
authors.initials: V
authors.lastname: Correia
authors.affiliation: Departamento de Engenharia Biólogica, da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Gama
authors.affiliation: Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|Ciber en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Valencia, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Gomez Ribelles
authors.affiliation: Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Senentxu
authors.initials: S
authors.lastname: Lanceros-Mendez
mesh_terms: D000818:Animals; D019149:Bioreactors; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism*; D002356:Cartilage / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D002461:Cell Line, Transformed; D005109:Extracellular Matrix / Q000737:chemistry*; D005337:Fibrin / Q000737:chemistry; D051379:Mice; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C016240:polycaprolactone; D005337:Fibrin
keywords: biomaterials; bioreactor; fatigue testing; fibrin; poly-ɛ-caprolactone