Stimulation of osteoblasts using rest periods during bioreactor culture on collagen-glycosaminoglycan scaffolds.

Osteoblasts respond to mechanical signals which play a key role in the formation of bone however, after extended periods of stimulation they become desensitised. Mechanosensitivity has been shown to be restored by the introduction of resting periods between loadings. The aim of this study was to analyse the effect of rest periods on the response of osteoblast-like cells seeded on collagen-glycosaminoglycan (CG) scaffolds in a flow perfusion bioreactor up to 14 days.

Osteoblast response to rest periods during bioreactor culture of collagen-glycosaminoglycan scaffolds.

Flow perfusion bioreactors have been shown to enhance fluid transport and improve cell viability throughout tissue-engineered bone constructs. Furthermore, osteoblasts have been shown to be stimulated by flow during bioreactor culture, although the optimum flow regime to promote an osteogenic response has yet to be found. One problem is that bone cells lose their ability to respond to stimulation; however, mechanosensitivity can be restored by introducing resting periods between bouts of loading.

Development of a biomimetic collagen-hydroxyapatite scaffold for bone tissue engineering using a SBF immersion technique.

The objective of this study was to develop a biomimetic, highly porous collagen-hydroxyapatite (HA) composite scaffold for bone tissue engineering (TE), combining the biological performance and the high porosity of a collagen scaffold with the high mechanical stiffness of a HA scaffold. Pure collagen scaffolds were produced using a lyophilization process and immersed in simulated body fluid (SBF) to provide a biomimetic coating. Pure collagen scaffolds served as a control.

Design and validation of a dynamic flow perfusion bioreactor for use with compliant tissue engineering scaffolds.

In tissue engineering, flow perfusion bioreactors can be used to enhance nutrient diffusion while mechanically stimulating cells to increase matrix production. The goal of this study was to design and validate a dynamic flow perfusion bioreactor for use with compliant scaffolds. Using a non-permanent staining technique, scaffold perfusion was verified for flow rates of 0.