Abstract
Platelet releasate (PR) has been used in regenerative medicine because it contains cell growth factors such as transforming growth factor-β (TGF-β) and platelet-derived growth factor (PDGF) that are effective in regenerating periodontal tissue. There have been many clinical reports on the use of PR, which is prepared by concentrating and processing human platelets, but the biological effects of PR on cells have not been fully clarified. Hence, to ascertain the effects of PR on periodontal tissue-derived cultured cells, TGF-β1 expression was measured using RT-PCR and ELISA and cell proliferation activity was assessed by monolayer and three-dimensional (3-D) culture methods. The results showed that the cell proliferation activities of periodontal tissue-derived human gingival fibroblasts (HGF), vascular endothelial cells (HVEC), epithelial cells (HEC), and periodontal ligament fibroblasts (HPLF) were greater with PR compared to cells cultured without PR. Next, the effects of PR on the cell proliferation activity of HGF and HPLF were investigated by the 3-D culture method using collagen matrix. The results showed that when compared to the no addition of PR, there were increases in cell proliferation rates on addition of PR (HGF : 2.66 times, HPLF : 4.37 times). Furthermore, when PR was added to PR-treated HPLF, the expression of TGF-β1 mRNA (3.38 times) and the production of TGF-β1 (24, 48, 72h PR FCM : 10.76, 12.15, 13.02ng/ml) by these cells increased.
The above findings show that PR facilitates the growth of cells that make up damaged periodontal tissue, and when scaffolding (collagen matrix) is provided, even more stable cellular proliferation is achieved. Also, since PR increases the production of TGF-β1, a growth factor important for periodontal regeneration, to levels sufficient to meet the conditions necessary for tissue regeneration, PR appears to be useful for regenerating periodontal tissue in vitro.
