title: Human periosteal-derived cell expansion in a perfusion bioreactor system: proliferation, differentiation and extracellular matrix formation.
abstract: Perfusion bioreactor systems have shown to be a valuable tool for the in vitro development of three-dimensional (3D) cell-carrier constructs. Their use for cell expansion, however, has been much less explored. Since maintenance of the initial cell phenotype is essential in this process, it is imperative to obtain insight into the bioreactor-related variables determining cell fate. Therefore, this study investigated the influence of fluid flow-induced shear stress on the proliferation, differentiation and matrix deposition of human periosteal-derived cells in the absence of additional differentiation-inducing stimuli; 120 000 cells were seeded on additive manufactured 3D Ti6Al4V scaffolds and cultured for up to 28 days at different flow rates in the range 0.04-6 ml/min. DNA measurements showed, on average, a three-fold increase in cell content for all perfused conditions in comparison to static controls, whereas the magnitude of the flow rate did not have an influence. Contrast-enhanced nanofocus X-ray computed tomography showed substantial formation of an engineered neotissue in all perfused conditions, resulting in a filling (up to 70%) of the total internal void volume, and no flow rate-dependent differences were observed. The expression of key osteogenic markers, such as RunX2, OCN, OPN and Col1, did not show any significant changes in comparison to static controls after 28 days of culture, with the exception of OSX at high flow rates. We therefore concluded that, in the absence of additional osteogenic stimuli, the investigated perfusion conditions increased cell proliferation but did not significantly enhance osteogenic differentiation, thus allowing for this process to be used for cell expansion. Copyright © 2014 John Wiley & Sons, Ltd.
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Department of Materials Engineering, Katholieke Universiteit Leuven, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Sonnaert
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Skeletal Biology and Engineering Research Centre, Katholieke Universiteit Leuven, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Papantoniou
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Biomedical Engineering Research Team, Groep T, Leuven Engineering College (Association Katholieke Universiteit Leuven), Belgium.
authors.forename: V
authors.initials: V
authors.lastname: Bloemen
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Department of Materials Engineering, Katholieke Universiteit Leuven, Belgium.|Biomechanics Research Unit, Université de Liege, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Kerckhofs
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Skeletal Biology and Engineering Research Centre, Katholieke Universiteit Leuven, Belgium.
authors.forename: F P
authors.initials: FP
authors.lastname: Luyten
authors.affiliation: Prometheus, Division of Skeletal Tissue Engineering, Katholieke Universiteit Leuven, Belgium.|Department of Materials Engineering, Katholieke Universiteit Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Schrooten
mesh_terms: D000497:Alloys; D019149:Bioreactors; D001854:Bone Marrow Cells / Q000166:cytology; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation; D019070:Cell Lineage; D049109:Cell Proliferation; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D010012:Osteogenesis; D010477:Perfusion; D010521:Periosteum / Q000166:cytology*; D033081:Shear Strength; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds; D014025:Titanium / Q000737:chemistry; D014057:Tomography, X-Ray Computed
chemical_list: D000497:Alloys; C031462:titanium alloy (TiAl6V4); D014025:Titanium
keywords: 3D; bioreactor; cell expansion; human periosteal-derived cells; nano CT; perfusion; tissue engineering