ABSTRACT
PURPOSE: We investigated the effects of low intensity ultrasound on the co-culture of human osteoblastic cells with endothelial cells and analysed cell proliferation and growth factors that might be involved in bone formation. METHODS: Cell culture system was established with human osteoblastic cells (SaOS-2) and primary isolated human umbilical vein endothelial cells (HUVEC). Low intensity ultrasound (1 MHz) treatment was administered for 20 minutes per day to each well for 4 consecutive days and its effects were determined by analysing cell proliferation activity, alkaline phosphatse and amount of growth factors such as basic fibroblast growth factor, transforming growth factor beta and transforming growth factor beta in the conditioned medium. RESULTS: Low intensity ultrasound treatment increased cell proliferation activity, level of the basic fibroblast growth factor and transforming growth factor beta in the co-culture system. The levels of alkaline phosphatase and transforming growth factor beta in the conditioned medium were not changed. We could not observe the change of cell proliferation or amount of various growth factors in a culture system of SaOS-2 or HUVEC. CONCLUSION: The low intensity ultrasound treatment can increase osteogenesis by certain interaction between the two cells and increase in bFGF and TGF beta participate in the process.