Investigation of host factor in early-onset peiodontitis on people with Down syndrome.

唐氏综合征（Down syndrome，DS）是一种常见的牙周病，是由牙龈卟啉单胞菌（Porphyromonas gingivalis）引起的成人牙周炎。牙龈上皮细胞（HGE）和成纤维细胞（HGF）组成的牙周组织作为一个前屏障，对病原微生物的入侵，包括牙龈卟啉单胞菌。然而，关于DS HGE对牙龈卟啉单胞菌感染的宿主反应的研究很少。本研究尝试改良HGE培养方法，以提高HGE培养的难度。通过体外侵袭实验和激光共聚焦显微镜观察，比较了牙龈卟啉单胞菌（P.gingivalis）感染DS和正常人（NS）的HGE和HGF的敏感性 ...更多信息 在无血清培养基中培养HGE。这种现象似乎是由于DS细胞中过量的染色体和减少的端粒导致细胞分裂改变和蛋白质合成恶化的维持。体外侵袭实验表明，DS来源的HGE比NS来源的HGE更易感染牙龈卟啉单胞菌。在这项研究中，我们发现更多的牙龈卟啉单胞菌粘附和侵袭的HGF从DS比HGF从NS。共聚焦显微镜观察显示，牙龈卟啉单胞菌侵入DS的HGE和HGF中的数量分别大于侵入NS的HGE和HGF中的数量，DS的HGE和HGF中的牙龈卟啉单胞菌的数量分别大于NS的HGE和HGF中的牙龈卟啉单胞菌的数量。表明DS的牙龈细胞比NS的牙龈细胞更易受牙龈卟啉单胞菌感染。总之，DS牙周组织的上皮细胞和成纤维细胞易受牙龈卟啉单胞菌感染，这些防御机制的改变可能是DS患者早发性重度牙周炎的原因。少

Person with Down syndrome (DS) has been known to be vulnerable in defence mechanism against infection and susceptible to an early-onset as well as a severe adult periodontitis caused by Porphyromonas gingivalis which is the most relevant pathogen of the periodontal disease. Gingival epithelial cells (HGE) and fibroblasts (HGF) consisting of periodontal tissue are acting as a front barrier against invasion of pathogenic microorganisms including P.gingivalis. However, there is little study on the host responses of DS HGE to P.gingivalis infection. In this research project, we tried to develop the modified culture method for improving difficulty of HGE culture. Then we compared the susceptibility of HGE and HGF derived from both DS and normal subjects (NS) to P.gingivalis infection by invasion assay and confocal microscopic observasion.The HGE derived from DS could be cultured more selectively in the medium without serum compared to medium containing serum, however, it was still difficult … More to culture HGE in the serum free medium. This phenomenon seems to be due to an excess chromosome and reduced telomere in DS cells causing altered cell division and maintenance by deteriorated protein synthesis. Invasion assay showed HGE derived from DS was more susceptible to P.gingivalis infection in vitro than HGE from NS.Recently, it was reported that P.gingivalis could adhere and invade to HGF. In this study, we showed that greater number of P.gingivalis had adhered and invaded to HGF from DS than to HGF from NS. These finding indicated that not only HGE but DS-derived HGF, existing beneath the epithelial cell layer, was more susceptible to P.gingivalis than these from NS.Confocal microscopic observation showed that the numbers of P.gingivalis -invaded into both HGE and HGF from DS were grater than those incaded into HGE and HGF from NS, respectively, suggesting that the gingival cells from DS are more susceptible to P.gingivalis infection in vitro than those cells from NS.In conclusion, epithelial cells and fibroblasts of DS periodontal tissue are susceptible to P.gingivalis infection, and these altered defence mechanism could be responsible for early-onset severe periodontitis in DS. Less