Abstract:

BACKGROUND: Recent studies have shown that co-cultured endothelial cells and osteoblasts are mutually promotive in bone tissues repair.
OBJECTIVE: To observe the effects of co-culture of endothelial cells and osteoblasts at different ratios on vasculogenesis and bone formation.
METHODS: Human umbilical vein endothelial cells and osteoblasts MG63 were isolated and cultured. Endothelial cells were co-cultured with osteoblasts at ratios of 1:0, 8:1, 4:1, 1:1, 1:4, 1:8, 0:1 in a 24-well plate, and monolayers of endothelial cells and osteoblasts were cultured alone respectively as controls. At 7, 14, 21 days after co-culture, cells growth condition, vascular endothelia growth factor level and alkaline phosphatase activity were observed and detected in each group.
RESULTS AND CONCLUSION: Cells grew well in each group in 21 days. At day 14, in the 1:8 group, osteoblasts began to cluster together. At day 21, the 1:4 group showed significantly more calcification nodules formed by Alizarin red staining than the 1:8 group, and no calcification nodules were seen in osteoblasts cultured alone. Alkaline phosphatase activity in the 1:4 group was significantly increased at the three time points (P < 0.05). The level of vascular endothelia growth factor in the 1:4 group began to increase at day 7 and reached its peak at day 21. These findings suggest that angiogenic effect is more effective when endothelial cells are co-cultured with osteoblasts at the ratio of 4:1, and osteogenic effect is more effective at the ratio of 1:4.