Immunological and molecular biological study of cytokine-network in periodontitis

我们研究了细胞因子对牙周致病菌的局部和系统作用，以阐明牙周炎中的免疫网络。辅助性T细胞（Helper T cell），调节免疫应答，已被分为1型辅助性T细胞（Type 1 helper T cell，Th 1）和2型辅助性T细胞（Type 2 helper T cell，Th 2）。Th 1增强细胞介导的免疫应答，而Th 2帮助体液免疫应答。这种差异是由细胞因子产生决定的，例如，Th 1产生IFN-γ和IL-2，Th 2产生IL-4、IL-5、IL-6和IL-10。本研究的目的是探讨牙周炎患者对牙周致病菌的免疫应答是否存在个体差异，以及个体差异对牙周炎临床状态的影响。IFN-γ的产生因个体而异。IFN-γ的产生依赖于单核细胞产生IL-12的能力。由于IFN-γ高、低产生者牙周炎的严重程度无明显差异，因此尽管个体间对牙周致病菌的免疫应答存在差异，但不能根据Th 1或Th 2的极化来判断牙周炎的易感性。

We have examined local and systematic function of cytokines against periodontopathic bacteria to clarify cytokine-network in periodontitis.Helper T cells, which regulate immune responses, have been divided into Type1 helper T cell(Th1)and Type2 helper T cell(Th2). Th1 augments cell-mediated immune responses, and Th2 helps humoral immune responses. This difference is determined by cytokine production, for example, Th1 produces IFN-γ and IL-2, Th2 produces IL-4, IL-5, IL-6 and IL-10. The aim of our study in this year was to examine whether individual diversities exist on not in immune responses against periodontopathic bacteria, and how individual diversities affect the clinical status in periodontitis.Periheral blood T cells produce IFN-γ by stimulation with periodontopathic bacteria. IFN-γ production varied among individuals. The production of IFN-γ was dependent on the ability of monocytes to produce IL-12.As the severity of periodontitis was not different between IFN-γ high and low producer, we could not determine the susceptibility of periodontitis based on the polarization of Th1 or Th2, although immune response against periodontopathic bacteria varied among individuals.