The study of inflammatory and defensive mechanisms in otitis media with effusion.

本课题通过局部接种KLH、脂多糖（LPS）和脂磷胆酸（LTA），研究了大鼠模型中耳趋化因子、细胞因子和细胞粘附分子的体内诱导和调控。同时检测中耳黏膜mRNA的表达。首先，我们检测了细胞粘附分子（CAM）在大鼠免疫介导的中耳炎中的表达，以及这些CAM在暴露于中耳积液（MEE）时外周血多形核白细胞（PMN）和淋巴细胞中的调节。CAM的表达对中耳炎的发生具有重要意义。此外，我们认为浸润的PMN与MEE之间的相互作用可能会改变中耳腔炎症过程中CAM的表达。趋化因子对中性粒细胞具有趋化激活作用，可能参与中耳炎症的发病机制。本研究通过局部接种LPS和LTA对中耳灌洗液中趋化因子的产生及其在中耳黏膜中的表达进行了研究。与革兰氏阴性内毒素脂壁酸（LTA）相反，脂壁酸（LTA）作为革兰氏阴性内毒素存在于这层脂多糖中，脂壁酸（LTA）存在于革兰氏阳性细菌的这层内。LTA已被证明在细菌感染的开始和进展中起着重要作用。在LPS或LTA刺激下，中耳灌洗中趋化因子的产生具有时间和剂量依赖性。在生产高峰期，使用聚合酶链反应评估细胞因子和趋化因子mRNA的表达，在中耳粘膜中相当可观。本研究利用大鼠体内模型研究中耳腔促炎细胞因子的特征，拓展了细胞因子在中耳炎初期的功能概念。

In this project, in vivo induction and regulation of chemokine, cytokines and cell adhsion molecules in the middle ear were investigated using topical inoculation with KLH,lopopolysaccharide (LPS) and Lipoteichoic acid (LTA) in rat model. The expressions of mRNA in the middle ear mucosa was also examined.At first, we examined the expression of cell adhesion molecules (CAM) in immune-mediated otitis media in the rat, as well as the regulation of these CAM in peripheral blood polymorphonuclear leukocytes (PMN) and lymphocytes upon exposure to middle ear effusion (MEE). The expression of CAM was important for the initiation of otitis media. Moreover, it ws thought that the interaction between the infiltrated PMN and MEE may modify the CAM's expression during the inflammatory process in the middle ear cavity.Chemokine possesses chemotactic-activating properties toward neutrophils, and may contribute to the pathogenesis of middle ear inflammations. We investigated the production of chemokine in middle ear lavage and that gene expression in the middle mucosa using topical inoculation with LPS and LTA in the rat in vivo model. In contrtast to LPS as gram-negative endotoxin, lipoteichoic acid (LTA) is present within this layr of LPS as gram-negative endotoxin, lipoteichoic acid (LTA) is present within this layr of mo gram-positive bacteria. LTA has been shown to play a sigificant role in the initiation and progression of bacterial infection. Chemokine in middle ear lavage showed time-and dose-dependent production under LPS or LTA stimulation. At the time of peak production, the expression of cytokines and chemokine mRNA,evaluated using polymerase chain reaction, was considerable in the middle ear mucosa.This investigation of the characteristics of proinflammatory cytokines in the middle ear cavity using rat in vivo model has extended the functional concept of cytokines at the initial stage otitis media.