title: Orderly osteochondral regeneration in a sheep model using a novel nano-composite multilayered biomaterial.
abstract: The objective of this article was to investigate the safety and regenerative potential of a newly developed biomimetic scaffold when applied to osteochondral defects in an animal model. A new multilayer gradient nano-composite scaffold was obtained by nucleating collagen fibrils with hydroxyapatite nanoparticles. In the femoral condyles of 12 sheep, 24 osteochondral lesions were created. Animals were randomized into three treatment groups: scaffold alone, scaffold colonized in vitro with autologous chondrocytes and empty defects. Six months after surgery, the animals were sacrificed and the lesions were histologically evaluated. Histologic and gross evaluation of specimens showed good integration of the chondral surface in all groups except for the control group. Significantly better bone regeneration was observed both in the group receiving the scaffold alone and in the group with scaffold loaded with autologous chondrocytes. No difference in cartilage surface reconstruction and osteochondral defect filling was noted between cell-seeded and cell-free groups. In the control group, no bone or cartilage defect healing occurred, and the defects were filled with fibrous tissue. Quantitative macroscopic and histological score evaluations confirmed the qualitative trends observed. The results of the present study showed that this novel osteochondral scaffold is safe and easy to use, and may represent a suitable matrix to direct and coordinate the process of bone and hyaline-like cartilage regeneration. The comparable regeneration process observed with or without autologous chondrocytes suggests that the main mode of action of the scaffold is based on the recruitment of local cells.
authors.affiliation: Laboratorio di Biomeccanica, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10-40136 Bologna, Italy. e.kon@biomec.ior.it
authors.forename: Elizaveta
authors.initials: E
authors.lastname: Kon
authors.forename: Marco
authors.initials: M
authors.lastname: Delcogliano
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Filardo
authors.forename: Milena
authors.initials: M
authors.lastname: Fini
authors.forename: Gianluca
authors.initials: G
authors.lastname: Giavaresi
authors.forename: Silvia
authors.initials: S
authors.lastname: Francioli
authors.forename: Ivan
authors.initials: I
authors.lastname: Martin
authors.forename: Daniele
authors.initials: D
authors.lastname: Pressato
authors.forename: Elena
authors.initials: E
authors.lastname: Arcangeli
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Quarto
authors.forename: Monica
authors.initials: M
authors.lastname: Sandri
authors.forename: Maurillo
authors.initials: M
authors.lastname: Marcacci
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D040761:Biomimetic Materials; D001861:Bone Regeneration; D002358:Cartilage, Articular / Q000293:injuries* / Q000473:pathology / Q000601:surgery*; D002478:Cells, Cultured / Q000637:transplantation; D019902:Chondrocytes / Q000166:cytology / Q000637:transplantation; D004195:Disease Models, Animal; D005260:Female; D005269:Femur / Q000601:surgery; D007718:Knee Injuries / Q000628:therapy; D053761:Nanocomposites; D012756:Sheep; D054457:Tissue Scaffolds; D014945:Wound Healing
chemical_list: D001672:Biocompatible Materials