牙龈卟啉单胞菌的牙龈蛋白酶K-caspase样亚基的表达与青春期龈炎的临床相关性  

Clinical association of gingipain K-caspase like subdomain expression of Porphyromonas gingivalis with puberty gingivitis

作　　者：陈旭[1] 宗志红[2] 潘亚萍[3] 

机构地区：[1]中国医科大学口腔医学院儿童口腔科,沈阳110002 [2]中国医科大学生化实验室 [3]中国医科大学口腔医学院牙周科

出　　处：《中华口腔医学杂志》2007年第2期96-99,共4页Chinese Journal of Stomatology

基　　金：国家自然科学基金(30371542);辽宁省教育厅高等学校科学研究项目计划(05L550)

摘　　要：目的检测并比较青春期龈炎的牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)临床分离株的分泌蛋白和菌体蛋白中牙龈蛋白酶 K(gingipain K,Kgp)-caspase 样亚基的表达强度及酶活性,揭示 Kgp 与青春期龈炎之间可能存在的致病关系。方法检测并记录36例14～17岁的青春期龈炎患者的牙龈指数、龈沟出血指数及探诊深度,取龈下菌斑进行 Pg 的分离培养,16S rRNA PCR 法鉴定。将获得的10个 Pg 临床分离株复苏,在对数生长期末提取分泌蛋白和菌体蛋白,测定其酶活性,并用Kgp-caspase 样亚基的单克隆抗体进行 Western blot 检测。Kgp 的表达强度及酶活性与各牙周指数之间的相关关系用等级相关系数。结果青春期龈炎的 Pg 临床分离株的分泌蛋白和菌体蛋白中,Kgp-caspase 样亚基的表达强度及酶活性与各牙周指数的大小呈正相关关系,差异有统计学意义(P<0.05)。结论青春期龈炎龈下菌斑中 Pg 的 Kgp 十分复杂,存在表现为低相对分子质量形式的caspase 样活性分子,这些细胞内功能蛋白分子将影响 Pg 和宿主间的相互作用;Kgp 对青春期龈炎有一定的致病作用。Objective To detect and compare the activity and intensity of gingipain K （Kgp）- caspase like subdomain in culture medium and cell extract of Porphyromonas gingivalis （Pg） isolates in puberty gingivitis and to reveal the possible association of Kgp with puberty gingivitis. Methods Thirty-six children of 14 to 17 years old were enrolled in this study. Clinical parameters including gingival index（GI）, sulcus bleeding index （SBI） and probing depth （PD） were evaluated. Subgingival plaque samples were collected and Pg isolates were obtained. 16S rRNA PCR was used to confirm Pg clinical isolates. Bacteria were grown in batches of BHI base and harvested at the end of log-phase growth. Culture fractions （ culture medium and cell extract） of 10 Pg isolates were performed with SDS-PAGE and Western blot technique using primary antibody against specific Kgp-caspase like subdomain. Activity of Kgp in both samples was detected as well. The data were statistically analyzed using SPSS 11.5 software. The relationship between the Kgp intensity/activity of Kgp and the clinical parameters was statistically analyzed using Spearman correlation coefficient. Results There was positive correlation between the intensity/activity of Kgp and the clinical parameters （P 〈0. 05）. Conclusions The Kgp in clinical isolates of Pg from puberty gingivitis is in complicated forms. Caspase-like molecules with low molecular weight may exist as intracellular functional protein molecules which can affect the interaction between Pg and host. Kgp was contributes in certain degree to the pathogenesis of puberty gingivitis.

关 键 词：龈紫单胞菌 龈炎 牙龈蛋白酶K 

分 类 号：R781.4[医药卫生—口腔医学]