Detection and Change of Secretory Leukocyte Protease Inhibitor Produced by Gingival Epithelial Cells in Periodontal Disease Progression.

本研究的目的是检测牙周上皮细胞中分泌性白细胞蛋白水解酶抑制物(SLPI)，并探讨其与牙周临床参数及牙周下菌斑中病原菌存在的可能关系。采用免疫细胞化学方法对冰冻切片和培养的健康牙周上皮细胞进行SLPI检测。用IL-1、β(0-100U/ml)、TNF-*(0-1000 ng/ml)和细胞外小泡(ECV)(0-100mug/ml)从放线杆菌(A.A)、牙龈假单胞菌(P.G)、夹心酶联免疫吸附试验检测培养的牙龈上皮细胞培养上清液中的中间普氏杆菌(P.i)、SLPI。牙周上皮细胞在无柄条件下将SLPI分泌到培养液中。随着TNF-*浓度的增加，SLPI的分泌受到明显抑制。同时，随着P.G ECV浓度的增加，SLPI的分泌也受到明显抑制。检测10例成人牙周炎患者GCF中SLPI水平和中性粒细胞弹性蛋白酶(NE)活性，并对牙菌斑标本进行8种牙周病原菌的DNA探针检测。在32个被检查的部位中，SLPI水平与GCF量和牙周炎的存在呈正相关。结果表明，牙周组织的蛋白水解性损伤可能与牙周组织中活性蛋白水解酶抑制物的减少有关。

The purpose of the present research project was to detect the secretory leukocyte protease inhibitor (SLPI) in gingival epithelial cells and to clarify the possible relationship between SLPI in gingival crevicular fluid (GCF) and the periodontal clinical parameters or the presence of periodontopathic bacteria in subgingival plaque.SLPI was immunocytochemically detected on frozen sectioned gingival epithelium and cultured gingival epithelial cells from healthy gingiva.After four hours incubation with IL-1*, beta (0-100U/ml), TNF-*(0-1,000ng/ml), and extracellular vesicles (ECV) (0-100mug/ml) from Actinobacillus actinomycetemcomitans (A.a), Porphiromonas gingivalis (P.g), and Prevotella intermedia (P.i), SLPI in supernatant of cultered gingival epithelial cells was measured using sandwich enzyme linked immunosorbent assay. Gingival epithelial cells secreted SLPI into culture medium under non stumuli. The secretion of SLPI was significantly suppressed under the increasing concentration of TNF-*. And the secretion of SLPI was also significantly suppressed under the increasing concentration of P.g ECV.SLPI levels and neutrophil elastase (NE) activity in GCF were measured and subgingival plaque samples were tested for the presence of eight periodontopathic bacteria by DNA probe analysis in ten adult periodontitis patients. In thirty two examined sites, the SLPI levels were positively associated with the GCF volume and the presence of gingival inflammation. Statiscally significant negative correlations were found between SLPI levels and the presence of P.g, Bacreroides forsythus and Treponema denticola, whereas, the NE activity increased in the presence of the bacteria.The results demonstrated that the bacteria with the capacity to produce proteolytic enzymes degraeded or inactivated the protease inhibitor, suggesting that the proteolytic damage of periodontal tissue might be caused by the decrease of active protease inhibitor.