Elucidation of new adhesion mechanism between neutrophils and gingival epithelial cells via thrombomodulin

在牙周炎患者的龈沟液中检测到释放的血栓调节素。牙龈上皮细胞在细胞表面表达血栓调节蛋白。在本研究中，我们研究了嗜中性粒细胞蛋白酶对上皮血栓调节蛋白的影响，以及细胞密度对外周血组织T淋巴细胞免疫反应的影响。中性粒细胞蛋白酶，弹性蛋白酶，而不是组织蛋白酶G，在口腔上皮细胞上释放血栓调节蛋白。这种影响发生在早期阶段。另一方面，早期释放的血栓调节素与弹性酶的细胞毒性无关。外周组织中的T细胞接触密度小于淋巴器官或血流中的T细胞接触密度。外周组织中较低的T细胞密度提出了一个问题，即外周组织中孤立T细胞的反应是否以与彼此更一致接触的T细胞相同的方式维持。我们研究了细胞间接触在维持与TCR/CD28信号传导相关的T细胞应答中的意义。细胞间接触的缺失导致T细胞的无应答状态的诱导，细胞间接触CD54提前通过ICAM-1进行酪氨酸磷酸化似乎是维持T细胞对CD3/CD28信号的应答所必需的

Released thrombomodulin has been detected in gingival crevicular fluid with periodontitis from periodontal patients. Gingival epithelial cells express thrombomodulin on their cell surface. In the present study, we investigated the influence of epithelial thrombomodulin by neutrophil protease and the immunoresponse of T lymphocytes in peripheral tissue by the difference of cell density. Neutrophil protease, Elastase but not cathepsin G, released thrombomodulin on oral epithelial cells. The effects occurred in the early phase. On the other hand, released thrombomodulin in the early phase was not related with cytotoxicity by elastase.T cell contact density in peripheral tissues is less than that in lymphoid organs or in the blood stream. The lower density of T cells in peripheral tissues raises a question as to whether the responses of solitary T cells in peripheral tissue are maintained in the same manner as T cells which are more consistently in contact with one another. We investigated the significance of cell-cell contact in the maintenance of T cell response related to TCR/CD28 signaling. The loss of the cell-cell contact results in the induction of a state of unresponsiveness of T cells and the tyrosine phosphorylation through ICAM-1 by cell-cell contact CD54 in advance seemed to be necessary to maintain T cell response to CD3/CD28 signaling