Possible Role of Gingival Epithelial Cells in Host Defense Mechanism of Periodontal Disease Progression

本研究的目的是检测分泌性白细胞蛋白酶抑制物(SLPI)和IL-1受体拮抗剂(IL-1ra)在牙周上皮细胞中的表达，探讨其与牙周临床参数的关系。测定15例成人牙周炎患者牙周组织中SLPI、α-1-蛋白酶抑制物(α-1-PI)水平和中性粒细胞弹性蛋白酶(NE)活性，并对牙周临床参数进行检测。在30个检查部位中，牙周炎部位的样本中SLPI、α1-PI、NE和GCF值均显著高于健康部位的样本。SLPI、α_1-PI和NE与探查深度相关。NE、α-1-PI与c-…升高显著相关更多的临床型依恋缺失。为明确IL-1和IL-1ra在人牙周角质形成细胞中的表达，采用酶联免疫吸附试验和逆转录聚合酶链式反应(RT-α)方法，研究了培养的人牙周角质形成细胞中IL-1α和IL-1ra蛋白的产生和表达。此外，我们还用免疫组织化学方法研究了IL-1α和IL-1ra在正常和炎症牙龈上皮细胞中的表达。细胞相关IL-1α水平在肿瘤坏死因子-α刺激下显著升高，而条件培养液中IL-1α水平和IL-1ra蛋白水平不受肿瘤坏死因子-α影响。逆转录聚合酶链式反应显示，IL-1α和细胞内IL-1raα转录本在肿瘤坏死因子-RNA刺激下表达增强。此外，免疫组织化学显示IL-1ra在牙龈上皮细胞中有表达，而IL-1α在牙周组织中无表达。提示人牙周角质形成细胞表达IL-1α和IL-1ra，可能参与了IL-1α和IL-1ra对牙周病炎症的调控。较少

The purpose of the present research project was to detect the expression of secretory leukocyte protease inhibitor (SLPI) and IL-1 receptor antagonist (IL-1ra) in gingival epithelial cells and to clarify the possible relationship between SLPI in gingival crevicular fluid (GCF) and the periodontal clinical parameters.SLPI was immunocytochemically detected on frozen-sectioned gingival epithelium and expressed on the surface and inside of cultured gingival keratinocytes from healthy gingiva. The levels of SLPI and α1-protease inhibitor (α1-PI) and neutrophil elastase (NE) activity in GCF were measured and periodontal clinical parameters were examined in fifteen adult periodontitis patients. In thirty examined sites, significantly higher amounts of SLPI, α1-PI, NE and GCF were consistently obtained in samples from periodontitis sites than in samples from healthy sites. SLPI, α1-PI and NE were found to correlate with probing depth. NE andα1-PI were significantly correlated with increasing c … More linical attachment loss. These results suggested that SLPI andα1-PI may be related to the inflammation in periodontitis sites.To clarify the expression of IL-1 and IL-1ra in human gingival keratinocytes, we studied the protein production and mRNA expression of IL-1α and IL-1ra in human cultured gingival keratinocytes using enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction (RT-PCR). Furthermore, we studied immunohistochemically the presence of IL-1αand IL-1ra in the epithelium of healthy and inflamed gingiva. The level of cell-associated IL-1α was significantly increased under stimulation of TNF-α, while the level of IL- 1α in conditioned medium and the levels of IL-1ra protein were not influenced by TNF-α. IL-1α and intracellular IL-1ra mRNA transcripts were enhanced under stimulation with TNF-αby RT-PCR. Furthermore, the presence of IL-1ra, but not IL-1α, found by immunohistochemistry in the epithelium of gingiva. These results indicated that human gingival keratinocytes expressed IL-1αand IL-1ra, and may be involved in the regulation of inflammation of periodontal disease by IL-1αand IL-1ra. Less