Platelet-rich Plasma Reverses the Inhibition of Tenocytes and Osteoblasts in Tendon-Bone Healing

The purpose of this study was to investigate the effect of platelet-rich plasma on the proliferation of osteoblasts and tenocytes in tendon-bone healing. We cultured osteoblasts and tenocytes in an indirect coculture system with Transwell filters (Merck Millipore, Billerica, Massachusetts). The proliferation was examined using Cell Counting Kit-8 (Dojindo Chemistry Research Institute, Kumamoto, Japan). Four groups were studied: group 1, one cell type cultured without platelet-rich plasma; group 2, two cell types cultured together in an indirect coculture system without platelet-rich plasma; group 3, cells in the outer chamber and platelet-rich plasma in the inner chamber; and group 4, two different cell types in each of the 2 chambers with platelet-rich plasma in the inner chamber. The proliferation rates of groups 3 and 4 were the highest, followed by group 1 and then group 2, which was the lowest. Platelet-rich plasma abolishes the inhibition of osteoblasts or tenocytes in an indirect coculture system and improves the cell proliferation rate.