title: A comparison of bioreactors for culture of fetal mesenchymal stem cells for bone tissue engineering.
abstract: Bioreactors provide a dynamic culture system for efficient exchange of nutrients and mechanical stimulus necessary for the generation of effective tissue engineered bone grafts (TEBG). We have shown that biaxial rotating (BXR) bioreactor-matured human fetal mesenchymal stem cell (hfMSC) mediated-TEBG can heal a rat critical sized femoral defect. However, it is not known whether optimal bioreactors exist for bone TE (BTE) applications. We systematically compared this BXR bioreactor with three most commonly used systems: Spinner Flask (SF), Perfusion and Rotating Wall Vessel (RWV) bioreactors, for their application in BTE. The BXR bioreactor achieved higher levels of cellularity and confluence (1.4-2.5x, p < 0.05) in large 785 mm(3) macroporous scaffolds not achieved in the other bioreactors operating in optimal settings. BXR bioreactor-treated scaffolds experienced earlier and more robust osteogenic differentiation on von Kossa staining, ALP induction (1.2-1.6×, p < 0.01) and calcium deposition (1.3-2.3×, p < 0.01). We developed a Micro CT quantification method which demonstrated homogenous distribution of hfMSC in BXR bioreactor-treated grafts, but not with the other three. BXR bioreactor enabled superior cellular proliferation, spatial distribution and osteogenic induction of hfMSC over other commonly used bioreactors. In addition, we developed and validated a non-invasive quantitative micro CT-based technique for analyzing neo-tissue formation and its spatial distribution within scaffolds.
authors.affiliation: Department of Mechanical Engineering, Faculty of Engineering, National University of Singapore, Centre for Biomedical Materials Applications and Technology, Singapore.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Swee Hin
authors.initials: SH
authors.lastname: Teoh
authors.forename: Erin Yiling
authors.initials: EY
authors.lastname: Teo
authors.forename: Mark Seow
authors.initials: MS
authors.lastname: Khoon Chong
authors.forename: Chong Woon
authors.initials: CW
authors.lastname: Shin
authors.forename: Foo Toon
authors.initials: FT
authors.lastname: Tien
authors.forename: Mahesh A
authors.initials: MA
authors.lastname: Choolani
authors.forename: Jerry K Y
authors.initials: JK
authors.lastname: Chan
mesh_terms: D019149:Bioreactors; D001842:Bone and Bones / Q000187:drug effects / Q000502:physiology*; D002113:Calcification, Physiologic / Q000187:drug effects; D002130:Calcium Phosphates / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D018929:Cell Culture Techniques / Q000295:instrumentation*; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D053686:Fetal Stem Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D011091:Polyesters / Q000494:pharmacology; D023822:Tissue Engineering / Q000295:instrumentation*; D054457:Tissue Scaffolds / Q000737:chemistry; D055114:X-Ray Microtomography
chemical_list: D002130:Calcium Phosphates; D011091:Polyesters; C016240:polycaprolactone; C018392:tricalcium phosphate