Invasion and Adhesion of Periopathogens

超出所提供的空间。放线菌是一种非运动的革兰氏阴性兼性球芽孢杆菌，定植于人的口腔和上呼吸道。大量的微生物学、免疫学和临床证据表明放线菌与局限性青少年牙周炎和快速难治性牙周病的发病机制有关。这种病原体与其他严重的人类感染有关，如心内膜炎、软组织脓肿和最近的心血管疾病。牙周组织被认为是这些口腔外感染的宿主，尽管人们对这种病原体在组织中渗透和传播的机制知之甚少。体外对上皮细胞的侵袭已得到证实，这种牙周病原已定位于上皮细胞内，并在受感染个体的组织活检中发现于上皮亚细胞层。我们的实验室已经证明放线菌comitans利用微管进行细胞内运输并从上皮细胞中退出。这些数据表明，微管在放线菌的传播和运动中起着关键作用，并提供了细胞内病原体的宿主细胞分散可能涉及微管篡夺的第一个证据。为了进一步了解这种独特的相互作用，我们建议：1)鉴定和表征参与与微管相互作用的细菌大分子；2)表征与放线菌相互作用的上皮细胞微管紫外光的成分。这些成分的鉴定对于了解这种病原体在口腔中生存和扩散到更深组织的过程将是重要的。网站性能 ======================================== 节结束 ===========================================

EXCEED THE SPACE PROVIDED. Actinobacillus actinomycetemcomitans is a non-motile, gram-negative facultative coccobacillus which colonizes the human oral cavity and upper respiratory tract. Overwhelming microbial, immunological and clinical evidence implicates A. actinomycetemcomitans in the pathogenesis of localized juvenile periodontitis and cases of rapid and refractory periodontal disease. This pathogen has been associated with other serious human infections such as endocarditis, soft tissue abscesses, and more recently cardiovascular disease. The periodontium has been implicated as the reservoir of these extraoral infections, although little is known about the mechanisms this pathogen utilizes to infiltrate and disseminate in tissues. The invasion into epithelial cells in vitro is well established and this periodontopathogen has been localized inside epithelial cells and found in sub epithelial cell layers in tissue biopsy from infected individuals. Our laboratory has demonstrated that A. actinomycetemcomitans utilizes microtubules for intracellular trafficking and exit from epithelial cells. The data suggest that microtubules play a critical role in the spread and movement of A. actinomycetemcomitans and provide the first evidence that host cell dispersion of an intracellular pathogen may involve the usurpation ofmicrotubules. To further understand this unique interaction, we propose to 1) identify and characterize the bacterial macromolecule(s) that are involved in the interaction with microtubules and 2) characterize the component(s) of the epithelial cell microtubule asters that interact with A. actinomycetemcomitans. The identification of these components will be important in understanding the processes that this pathogen uses to survive in the oral cavity and disperse into deeper tissues. PERFORMANCE SITE ========================================Section End===========================================