title: An automated perfusion bioreactor for the streamlined production of engineered osteogenic grafts.
abstract: A computer-controlled perfusion bioreactor was developed for the streamlined production of engineered osteogenic grafts. This system automated the required bioprocesses, from the initial filling of the system through the phases of cell seeding and prolonged cell/tissue culture. Flow through chemo-optic micro-sensors allowed to non-invasively monitor the levels of oxygen and pH in the perfused culture medium throughout the culture period. To validate its performance, freshly isolated ovine bone marrow stromal cells were directly seeded on porous scaffold granules (hydroxyapatite/β-tricalcium-phosphate/poly-lactic acid), bypassing the phase of monolayer cell expansion in flasks. Either 10 or 20 days after culture, engineered cell-granule grafts were implanted in an ectopic mouse model to quantify new bone formation. After four weeks of implantation, histomorphometry showed more bone in bioreactor-generated grafts than cell-free granule controls, while bone formation did not show significant differences between 10 days and 20 days of incubation. The implanted granules without cells had no bone formation. This novel perfusion bioreactor has revealed the capability of activation larger viable bone graft material, even after shorter incubation time of graft material. This study has demonstrated the feasibility of engineering osteogenic grafts in an automated bioreactor system, laying the foundation for a safe, regulatory-compliant, and cost-effective manufacturing process.
authors.affiliation: Orthopaedic Research Laboratory, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital, Institute of Clinical Research, University of Southern Denmark, DK-5000, Odense C, Denmark.
authors.forename: Ming
authors.initials: M
authors.lastname: Ding
authors.affiliation: Orthopaedic Research Laboratory, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital, Institute of Clinical Research, University of Southern Denmark, DK-5000, Odense C, Denmark.
authors.forename: Susan S
authors.initials: SS
authors.lastname: Henriksen
authors.affiliation: Departments of Surgery and of Biomedicine, University Hospital Basel, Hebelstrasse 20, ZLF, Room 405, 4031, Basel, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Wendt
authors.affiliation: Orthopaedic Research Laboratory, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital, Institute of Clinical Research, University of Southern Denmark, DK-5000, Odense C, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Overgaard
mesh_terms: D000818:Animals; D019149:Bioreactors; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism*; D018786:Bone Substitutes / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D005260:Female; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D010012:Osteogenesis; D011091:Polyesters / Q000737:chemistry*; D012756:Sheep; D023822:Tissue Engineering
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D011091:Polyesters; C485817:beta-tricalcium phosphate; C033616:poly(lactide); D017886:Durapatite
keywords: bioreactor; bone grafts; bone marrow stromal cells; bone regeneration; mesenchymal stem cells; tissue engineering