title: Promotion of osteoblast differentiation in 3D biomaterial micro-chip arrays comprising fibronectin-coated poly(methyl methacrylate) polycarbonate.
abstract: Due to the architecture of solid body tissues including bone, three-dimensional (3D) in vitro microenvironments appear favorable, since herein cell growth proceeds under more physiological conditions compared to conventional 2D systems. In the present study we show that a 3D microenvironment comprising a fibronectin-coated PMMA/PC-based micro-chip promotes differentiation of primary human osteoblasts as reflected by the densely-packed 3D bone cell aggregates and expression of biomarkers indicating osteoblast differentiation. Morphogenesis and fluorescence dye-based live/dead staining revealed homogenous cell coverage of the microcavities of the chip array, whereat cells showed high viability up to 14 days. Moreover, Azur II staining proved formation of uniform sized multilayered aggregates, exhibiting progressive intracellular deposition of extracellular bone matrix constituents comprising fibronectin, osteocalcin and osteonectin from day 7 on. Compared to 2D monolayers, osteoblasts grown in the 3D chip environment displayed differential mostly higher gene expression for osteocalcin, osteonectin, and alkaline phosphatase, while collagen type I remained fairly constant in both culture environments. Our results indicate that the 3D microenvironment, based on the PMMA biomaterial chip array promotes osteoblast differentiation, and hereby renders a promising tool for tissue-specific in vitro preconditioning of osteoblasts designated for clinically-oriented bone augmentation or regeneration.
authors.affiliation: Department of Prosthodontics, Dental School, University Hospital Freiburg, Freiburg, Germany.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Altmann
authors.forename: Thorsten
authors.initials: T
authors.lastname: Steinberg
authors.forename: Stefan
authors.initials: S
authors.lastname: Giselbrecht
authors.forename: Eric
authors.initials: E
authors.lastname: Gottwald
authors.forename: Pascal
authors.initials: P
authors.lastname: Tomakidi
authors.forename: Maria
authors.initials: M
authors.lastname: Bächle-Haas
authors.forename: Ralf-Joachim
authors.initials: RJ
authors.lastname: Kohal
mesh_terms: D000328:Adult; D000368:Aged; D002470:Cell Survival; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D005353:Fibronectins / Q000737:chemistry / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008297:Male; D055616:Microtechnology; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D011076:Polycarboxylate Cement / Q000737:chemistry / Q000378:metabolism*; D019904:Polymethyl Methacrylate / Q000737:chemistry / Q000378:metabolism*; D046888:Tissue Array Analysis / Q000295:instrumentation*; D023822:Tissue Engineering / Q000295:instrumentation*; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D005353:Fibronectins; D011076:Polycarboxylate Cement; C005506:polycarbonate; D019904:Polymethyl Methacrylate