IADR Abstract Archives
Osteogenic Cell Sheets Reinforced with Photofunctionalized Micro-thin Titanium
Objectives: Bone engineering is a promising strategy but not yet clinically applicable to reconstructing lost alveolar bone. Cell sheet technology has been used to deliver cells in single-sheet form with intact extracellular matrices in regenerative medicine. Photofunctionalization is a technology in which titanium surfaces are activated by ultraviolet (UV) light treatment immediately prior to use, and has been clinically proven effective due to the highly improved affinity of titanium to osteogenic cells. Here, we hypothesized that titanium-reinforced osteogenic cell sheets could be constructed for bone engineering. The purpose of this study is to identify the technical and material requirements for the advanced cell sheets and establish their functional phenotypes.
Methods: 50 mm-thick titanium plates containing apertures were prepared and roughened by acid etching, some of which were photofunctionalized with 12 min of UV treatment. Cell sheets were prepared by culturing rat calvarial periosteum-derived cells on temperature-responsive culture dishes and attached to titanium plates. The structural integrity between the attached cell sheets and titanium plates was examined by confocal microcopy and osteogenic phenotypes by ALP production and mineralization.
Results: Cell sheets needed to be double-sided and sandwich the titanium plate to form a stable cell sheet-titanium complex. Critically, titanium plates needed to be UV-photofunctionalized to ensure adherence and retention of cell sheets. Single-sided cell sheets or double-sided cell sheets on as-made titanium contracted and deformed within four days of incubation. Cell sheets on photofunctionalized titanium were structurally stable at least up to 14 days, developed the expected osteogenic phenotypes time-dependently (p<0.05). Successful construction of titanium-reinforced osteogenic cell sheets was associated with significantly increased cell attachment, retention, and expression of vinculin, an adhesion protein by photofunctionalization (p<0.05).
Conclusions: Construction of titanium-reinforced osteogenic cell sheets was conditionally feasible to safely and stably deliver a fully functional and custom-designed osteogenic device.
Methods: 50 mm-thick titanium plates containing apertures were prepared and roughened by acid etching, some of which were photofunctionalized with 12 min of UV treatment. Cell sheets were prepared by culturing rat calvarial periosteum-derived cells on temperature-responsive culture dishes and attached to titanium plates. The structural integrity between the attached cell sheets and titanium plates was examined by confocal microcopy and osteogenic phenotypes by ALP production and mineralization.
Results: Cell sheets needed to be double-sided and sandwich the titanium plate to form a stable cell sheet-titanium complex. Critically, titanium plates needed to be UV-photofunctionalized to ensure adherence and retention of cell sheets. Single-sided cell sheets or double-sided cell sheets on as-made titanium contracted and deformed within four days of incubation. Cell sheets on photofunctionalized titanium were structurally stable at least up to 14 days, developed the expected osteogenic phenotypes time-dependently (p<0.05). Successful construction of titanium-reinforced osteogenic cell sheets was associated with significantly increased cell attachment, retention, and expression of vinculin, an adhesion protein by photofunctionalization (p<0.05).
Conclusions: Construction of titanium-reinforced osteogenic cell sheets was conditionally feasible to safely and stably deliver a fully functional and custom-designed osteogenic device.