MICROBIAL/HOST IMMUNE REGULATION IN PERIODONTAL DISEASE

大量的人体微生物学和免疫学研究及实验 动物已将牙龈卟啉单胞菌确定为主要的 与牙周炎有关的病原体。现已确定该主机 对牙龈假单胞菌的免疫应答包括T细胞介导的 可在血清、宫腔液和唾液中检测到的抗体。 然而，全身和粘膜反应之间的关系，Th 细胞受到刺激，牙周炎不明显。因此，总体上， 这项建议的目的是确定全身和粘膜免疫 不同牙龈假单胞菌株诱导的免疫应答及Th的作用 这些反应中的细胞亚集以及它们对 疾病过程。这些研究将使用费舍尔大鼠作为 实验动物模型。具体地说，我们将确定：1)菌株 能诱导不同的系统和粘膜抗体反应； 2)不同的牙周血吸虫抗原和免疫途径 选择性刺激不同的Th细胞亚群；3)幼稚的能力 对比牙龈假单胞菌致敏的Th细胞以支持保护性体液 4)不同牙龈假单胞菌抗原和 免疫方案，以诱导对疾病具有保护作用的反应。 动物将面临牙龈假单胞菌菌株的挑战。系统性和 黏膜抗体反应将通过酶联免疫吸附试验和免疫印迹进行评估 分析。牙槽骨的破坏将通过手指来确定 放射摄影术。在其他研究中，老鼠将通过不同的途径进行免疫 与牙龈假单胞菌菌毛、血凝素、荚膜多糖或 脂多糖。治疗前将收集血清和唾液。 在整个实验过程中每隔一周进行一次。的水平和同种类型 将对抗体进行评估。脾和佩尔氏斑Th细胞将被 流式细胞仪分离鉴定细胞表面标志物及细胞因子 在信使核糖核酸和分泌蛋白的水平产生。抗原特异性Th 细胞亚群将过继转移到裸鼠体内 会受到牙龈假单胞菌的挑战。全身性和粘膜抗体 将对牙槽骨丢失的反应和程度进行评估。这些研究 将确定抗原特异性T细胞和它们的 牙周病的致病因素。遵循类似的协议， 用不同的牙龈假单胞菌抗原免疫大鼠，并进行评估 用来预防疾病。这些研究的结果将提供 更好地了解免疫系统和 牙龈假单胞菌的抗原，说明疾病的过程。此外， 拟议的调查将为未来的研究提供指导 为人类研制成人牙周炎疫苗。

Numerous microbiologic and immunologic studies in humans and experimental animals have established Porphyromonas gingivalis as one of the major pathogens associated with periodontitis. It has been established that host immune responses to P. gingivalis include T cell-mediated production of antibodies which can be detected in serum, crevicular fluid and saliva. However, the relationship between systemic and mucosal responses, the Th cells stimulated and periodontitis is not clear. Thus, the overall objective of this proposal is to determine the systemic and mucosal immune responses induced by different strains of P. gingivalis, the role of Th cell subsets in these responses and finally their contribution to the disease process. These studies will use the Fischer rat as the experimental animal model. Specifically, we will determine: 1) if strains of P. gingivalis induce different systemic and mucosal antibody responses; 2) if different antigens of P. gingivalis and the route of immunization selectively stimulate distinct Th cell subsets; 3) the ability of naive versus P. gingivalis- primed Th cells to support protective humoral responses; and 4) the ability of different P. gingivalis antigens and immunization regimens to induce responses protective against disease. Animals will be challenged with P. gingivalis strains. Systemic and mucosal antibody responses will be assessed by ELISA and Western blot analysis. Destruction of alveolar bone will be determined by digital radiography. In other studies, rats will be immunized by different routes with P. gingivalis fimbriae, hemagglutinin, capsular polysaccharide or lipopolysaccharide. Serum and saliva will be collected prior to treatment and every other week throughout the experiment. The level and isotype of antibody will be assessed. Splenic and Peyer's patch Th cells will be isolated and characterize for surface markers by FACS and for cytokine production at the levels of mRNA and secreted protein. Antigen-specific Th cell subsets will be adoptively transferred to nude Fischer rats which will be challenged with P. gingivalis. Systemic and mucosal antibody responses and levels of alveolar bone loss will be assessed. These studies will determine the mechanisms by which antigen-specific T cells and their factors contribute to periodontal disease. Following a similar protocol, rats will be immunized with different P. gingivalis antigens and assessed for protection against disease. The results of these studies will provide a better understanding of the interactions between the immune system and P. gingivalis antigens that account for the disease process. Furthermore, the proposed investigations will provide a guide for future studies in humans for the development of vaccines against adult periodontitis.