title: A differential pressure laminar flow reactor supports osteogenic differentiation and extracellular matrix formation from adipose mesenchymal stem cells in a macroporous ceramic scaffold.
abstract: We present a laminar flow reactor for bone tissue engineering that was developed based on a computational fluid dynamics model. The bioreactor design permits a laminar flow field through its specific internal shape. An integrated bypass system that prevents pressure build-up through bypass openings for pressure release allows for a constant pressure environment during the changing of permeability values that are caused by cellular growth within a porous scaffold. A macroporous ceramic scaffold, composed of zirconium dioxide, was used as a test biomaterial that studies adipose stem cell behavior within a controlled three-dimensional (3D) flow and pressure environment. The topographic structure of the material provided a basis for stem cell proliferation and differentiation toward the osteogenic lineage. Dynamic culture conditions in the bioreactor supported cell viability during long-term culture and induced cell cluster formation and extra-cellular matrix deposition within the porous scaffold, though no complete closure of the pores with new-formed tissue was observed. We postulate that our system is suitable for studying fluid shear stress effects on stem cell proliferation and differentiation toward bone formation in tissue-engineered 3D constructs.
authors.affiliation: Laboratory of Experimental Plastic and Reconstructive Surgery, Department of Plastic and Reconstructive Surgery, Hannover Medical School , Hannover, Germany .
authors.forename: Birgit
authors.initials: B
authors.lastname: Weyand
authors.forename: Cornelia
authors.initials: C
authors.lastname: Kasper
authors.forename: Meir
authors.initials: M
authors.lastname: Israelowitz
authors.forename: Christoph
authors.initials: C
authors.lastname: Gille
authors.forename: Herbert P
authors.initials: HP
authors.lastname: von Schroeder
authors.forename: Kerstin
authors.initials: K
authors.lastname: Reimers
authors.forename: Peter M
authors.initials: PM
authors.lastname: Vogt
keywords: 3D culture; bioreactor; bone tissue engineering; computer model; fluid dynamics; laminar flow; shear stress