title: Cell-laden and cell-free biopolymer hydrogel for the treatment of osteochondral defects in a sheep model.
abstract: The objective of the current study was to determine the suitability of cell-laden and cell-free alginate-gelatin biopolymer hydrogel for osteochondral restoration in a sheep model (n = 12). Four femoral defects per animal were filled with hydrogel (cHG) plus autologous chondrocytes (cHG + C) or periosteal cells (cHG + P) or gel only (cHG) or were left untreated (E). In situ solidification enabled instantaneous implant fixation. Sixteen weeks postoperatively, defect sites were processed for light microscopy and immunofluorescence. A modified Mankin and a semi-quantitative immunoreactivity score were used to evaluate histology and immunofluorescence, respectively. Defects after cHG + C were restored with smooth, hyaline-like neo-cartilage and trabecular subchondral bone. cHG + P and cHG treatments revealed slightly inferior regenerate morphology. Undifferentiated tissue was found in E. The histological score showed significant (p < 0.05) differences between all treatment groups. In conclusion, cHG induces satisfactory defect regeneration. Complete filling of the cavity in one step and subsequent rapid in situ solidification was feasible and facilitated graft fixation. Cell implantation might be beneficial, because cells seem to play a key role in histological outcome. Still, their contribution to the repair process remains unresolved because host cell influx takes place. The combination of alginate and gelatin, however, creates an environment capable of serving implanted and host cells for osteo-chondrogenic tissue regeneration.
authors.affiliation: Department of Orthopedic Surgery, Cartilage and Connective Tissue Research Laboratory, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Jan C
authors.initials: JC
authors.lastname: Schagemann
authors.forename: Christoph
authors.initials: C
authors.lastname: Erggelet
authors.forename: Hsi-Wei
authors.initials: HW
authors.lastname: Chung
authors.forename: Andreas
authors.initials: A
authors.lastname: Lahm
authors.forename: Haymo
authors.initials: H
authors.lastname: Kurz
authors.forename: Eike H
authors.initials: EH
authors.lastname: Mrosek
mesh_terms: D000464:Alginates / Q000737:chemistry; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D001704:Biopolymers / Q000737:chemistry*; D002021:Buffers; D002358:Cartilage, Articular / Q000166:cytology / Q000293:injuries / Q000637:transplantation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000637:transplantation; D024042:Collagen Type I / Q000737:chemistry; D005240:Feasibility Studies; D019085:Fluorescent Antibody Technique, Direct; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007719:Knee Joint / Q000601:surgery; D008422:Materials Testing; D023421:Models, Animal; D010521:Periosteum / Q000166:cytology; D012038:Regeneration; D034561:Sheep, Domestic / Q000601:surgery; D013997:Time Factors; D014182:Transplantation, Autologous / Q000379:methods; D016896:Treatment Outcome
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D001704:Biopolymers; D002021:Buffers; D024042:Collagen Type I; D006603:Hexuronic Acids; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020723:Glucuronic Acid