Matsuda N, Takemura A, Taniguchi S, Amano A, Shizukuishi S
Laboratory of Cell and Stress Biology, Japan Science and Technology Corporation, Nagasaki, Japan.
J Periodontol. 1996 Dec;67(12):1335-41. doi: 10.1902/jop.1996.67.12.1335.
The effects of a sonicated Porphyromonas gingivalis ATCC 33277 protein extract on the mitogenic and chemotactic responses of human periodontal ligament (PDL) cells to the recombinant human platelet-derived growth factor-BB homodimer (PDGF-BB) were examined in vitro. Proliferation of PDL cells was inhibited by P. gingivalis extract at concentrations higher than 10 micrograms/mL protein. At 100 micrograms/mL of P. gingivalis extract, cells did not proliferate. DNA synthesis in PDL cells, as revealed by [3H]-thymidine incorporation, was also inhibited by approximately 50% in the presence of 50 micrograms/mL P. gingivalis extract for 24 hours. In contrast, PDGF-BB at 1 ng/mL enhanced DNA synthesis in PDL cells, followed by maximum enhancement at concentrations higher than 10 ng/mL PDGF-BB. However, this mitogenic response to PDGF-BB was markedly reduced in the presence of 20 micrograms/mL of P. gingivalis extract and did not reach the maximum level even if PDGF-BB concentrations were increased to 250 ng/mL. PDL cells exhibited a chemotactic response to PDGF-BB at 1 ng/mL, which was also inhibited by pretreatment of the cells with P. gingivalis extract at 10 to 50 micrograms/mL. Scatchard analysis of a [125I]-PDGF binding assay demonstrated that PDL cells have both high and low PDGF binding affinity sites. Treatment of the cells with P. gingivalis extract decreased the number of PDGF-binding sites to approximately 35% of the control level, while it caused only a slight change in the affinities of both types of binding site. These results indicated that the P. gingivalis extract reduced mitogenic and chemotactic responses of human PDL cells, possibly through mechanisms involving a decrease in PDGF-binding capacity of these cells. Due to this inhibitory effect of P. gingivalis, the normal levels of PDGF in periodontal lesions may not be sufficient to promote periodontal regeneration through activation of PDL cell proliferation and migration. Therefore, the therapeutic use of PDGF-BB, as a supplement to pre-existing PDGF and as an adjunct, while also eliminating P. gingivalis from periodontal lesions, would help periodontal tissue regeneration.
体外研究了超声处理的牙龈卟啉单胞菌ATCC 33277蛋白提取物对人牙周膜（PDL）细胞对重组人血小板衍生生长因子 - BB同二聚体（PDGF - BB）的促有丝分裂和趋化反应的影响。当牙龈卟啉单胞菌提取物浓度高于10微克/毫升蛋白质时，PDL细胞的增殖受到抑制。在100微克/毫升的牙龈卟啉单胞菌提取物中，细胞不增殖。[3H] - 胸腺嘧啶核苷掺入显示，在存在50微克/毫升牙龈卟啉单胞菌提取物24小时的情况下，PDL细胞中的DNA合成也被抑制了约50%。相比之下，1纳克/毫升的PDGF - BB可增强PDL细胞中的DNA合成，在高于10纳克/毫升的PDGF - BB浓度时达到最大增强。然而，在存在20微克/毫升牙龈卟啉单胞菌提取物的情况下，对PDGF - BB的这种促有丝分裂反应明显降低，即使将PDGF - BB浓度增加到250纳克/毫升也未达到最大水平。PDL细胞对1纳克/毫升的PDGF - BB表现出趋化反应，用10至50微克/毫升的牙龈卟啉单胞菌提取物预处理细胞也可抑制这种趋化反应。[125I] - PDGF结合试验的Scatchard分析表明，PDL细胞具有高亲和力和低亲和力的PDGF结合位点。用牙龈卟啉单胞菌提取物处理细胞可使PDGF结合位点的数量减少至对照水平的约35%，而对两种类型结合位点的亲和力仅引起轻微变化。这些结果表明，牙龈卟啉单胞菌提取物降低了人PDL细胞的促有丝分裂和趋化反应，可能是通过降低这些细胞的PDGF结合能力的机制。由于牙龈卟啉单胞菌的这种抑制作用，牙周病变中PDGF的正常水平可能不足以通过激活PDL细胞增殖和迁移来促进牙周再生。因此，将PDGF - BB作为现有PDGF的补充剂和辅助剂进行治疗性使用，同时从牙周病变中消除牙龈卟啉单胞菌，将有助于牙周组织再生。
