Beauséjour A, Deslauriers N, Grenier D
Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec, Canada.
Infect Immun. 1997 Aug;65(8):3199-202. doi: 10.1128/iai.65.8.3199-3202.1997.
There are several indications suggesting that interleukin-1beta (IL-1beta) may play an important role in inflammatory periodontal diseases. We hypothesized that periodontal sites would represent a unique combination of both cellular sources of IL-1beta precursor (pro-IL-1beta) and microbial proteases and proposed that Treponema denticola, a suspected periodontal pathogen, would play a critical role in the inflammatory nature of adult chronic periodontitis by activating pro-IL-1beta. The aim of this study was thus to demonstrate the proteolytic cleavage and activation of the inactive precursor pro-IL-1beta by T. denticola. After incubation of bacterial cells with recombinant pro-IL-1beta, proteolytic cleavage was monitored by Western immunoblotting, and the biological activity of the digestion products was tested in a bioassay. We report here that T. denticola can cleave pro-IL-1beta to yield two fragments with molecular masses of 18 and 19 kDa. Cleavage products showed a dose-dependent biological activity in the thymocyte proliferation bioassay, and this activity was inhibited by anti-IL-1beta neutralizing antibodies. These results suggest that T. denticola may have a proinflammatory role in periodontal diseases.
有多种迹象表明，白细胞介素-1β（IL-1β）可能在炎症性牙周疾病中发挥重要作用。我们推测牙周部位可能是IL-1β前体（pro-IL-1β）的细胞来源与微生物蛋白酶的独特组合，并提出齿垢密螺旋体（一种可疑的牙周病原体）通过激活pro-IL-1β在成人慢性牙周炎的炎症性质中起关键作用。因此，本研究的目的是证明齿垢密螺旋体对无活性前体pro-IL-1β的蛋白水解切割和激活作用。在用重组pro-IL-1β孵育细菌细胞后，通过蛋白质免疫印迹法监测蛋白水解切割，并在生物测定中测试消化产物的生物活性。我们在此报告，齿垢密螺旋体可切割pro-IL-1β，产生分子量为18 kDa和19 kDa的两个片段。切割产物在胸腺细胞增殖生物测定中显示出剂量依赖性生物活性，并且这种活性被抗IL-1β中和抗体抑制。这些结果表明，齿垢密螺旋体可能在牙周疾病中具有促炎作用。
