P19 A 3-DIMENSIONAL, IN VITRO MODEL TO STUDY THE EFFECTS OF COMPRESSIVE LOADING ON OSTEOBLASTIC CELLS

摘要: Mechanical force is an osteoinductive factor that plays important role in bone growth and repair vivo (Carter et al. 1988). Many vitro studies have shown osteoblasts osteocytes respond to mechanical loads such as stretch fluid-flow induced shear stresses, with initiation of signalling pathways (Reilly al 2003). The underlying mechanisms by which cells signals are difficult investigate a 3-D environment, because reduced nutrient delivery difficulties analysis. We developing model analyse the effects compression on matrix forming system. Our uses polyurethane (PU) open cell foam scaffolds, MLO-A5 osteoblast-like (Kato 2001) sterile fluid filled biodynamic loading chamber (Bose). using proliferation assay (Promega) survive well proliferate PU scaffolds. Cell number after 15 days culture was four times 5 culture. To examine effect stimulation osteoblastic we seeded MLO-A5, kindly donated Dr. L. Bonewald, at densities 125,000 per scaffold cylinders, 10 mm thick 25 diameter. scaffolds were dynamically loaded 1Hz, 5% strain fluid-filled chamber. Loading applied for 2 hours day 5, 7 9 In between cycles, cultured incubator standard conditions. Preliminary data indicates survived but final compared unloaded controls 30%. However, stiffness (Young’s modulus) increased samples over time (days) may be indication production. Fluorescence microscopy indicated distributed dense clusters whereas evenly throughout scaffold. conclusion, this has potential answer questions about survival, distribution production 3-D, response signals.