Research in bone tissue engineering focuses on how mechanical forces can be used to improve bone matrix production. The group of Gwen Reilly is using a newly developed bone cell line which rapidly synthesizes matrix (in collaboration with the University of Kansas Missouri, USA). A system has been developed for studying the mechanical modulation of bone matrix formation in 3D using a cyclic compressive loading stimulus.
Polyurethane (PU) open cell foam scaffolds are seeded with bone cells under static conditions and loaded in compression at 1Hz, 5% strain in a sterile fluid-filled chamber, (Bose ElectroForce). Loading is applied for 2 hours per day at day 5, 10 and 15 of culture and cell-seeded scaffolds are assayed on days 10, 15 and 20 of culture.
Collagen content is 2 fold higher at days 15 and 20 in loaded samples compared with static controls and calcium content is 4 fold higher by day 20. Loaded samples also have higher stiffness in compression. The gene expression of the bone matrix proteins type I collagen, osteopontin and osteocalcin is also higher. This research is useful for the systematic investigation of modulators of in vitro matrix mineralisation by osteoblasts in mechanobiology and tissue engineering studies.