Studies on the virulence of Fillifactor alocis

Fillifactor alocis的毒力研究

• 批准号: 8467702
• 负责人: Hansel M. Fletcher
• 金额: $ 18.96万
• 依托单位: LOMA LINDA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-08 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8467702
• 关键词: Actinobacillus actinomycetemcomitans; Adherence; Animal Model; Apical; Apoptosis; Bacteria; Biological Models; Clinical; Coculture Techniques; Communities; Complex; Computer Simulation; Data; Development; Diagnostic; Disease; Endocytic Vesicle; Endodontics; Environment; Epithelial Cells; Forsythia; Fusobacterium; Genetic; Gingiva; Gingival Pocket; Goals; Growth; Health; Human; Immune response; Infection; Inflammation; Knowledge; Laboratories; Lead; Mass Spectrum Analysis; Mediating; Microbial Biofilms; Modeling; Molecular; Mono-S; Neuraminidase; Oral; Organism; Oxidative Stress; PAWR protein; Pathogenesis; Pathogenicity; Patients; Peptide Hydrolases; Periodontal Diseases; Periodontal Pocket; Periodontitis; Personal Communication; Phylogenetic Analysis; Play; Porphyromonas gingivalis; Prevention; Prevotella intermedia; Property; Proteome; Rattus; Refractory; Research; Resistance; Ribosomal RNA; Role; Structure; Structure of gingival sulcus; System; Techniques; Testing; Treponema denticola; Variant; Virulence; Virulence Factors; Work; base; design; in vivo; novel; novel therapeutic intervention; novel therapeutics; oral microbiome; pathogen; retinal rods; soft tissue; success

DESCRIPTION (provided by applicant): Bacteria in the periodontal pocket can develop complex sessile communities that play a significant role in infection-induced periodontal disease. Data emerging from the oral microbiome project is facilitating a shift in the paradigm for infection-induced periodontal diseases. Bacteria like Porphyromonas gingivalis, Prevotella intermedia, Aggregatibacter (Actinobacillus) actinomycetemcomitans, Tannerella forsythia and Treponema denticola have previously been demonstrated to be major pathogens associated with periodontal diseases. However, recent developments including novel, culture-independent techniques have allowed the identification of as-yet-culturable and fastidious organisms in patients suffering from periodontitis. Collectively, these studies have demonstrated that changes in periodontal status are associated with shifts in the composition of the bacterial community in the periodontal pocket. Filifactor alocis, a Gram-positive, asaccharolytic, obligate anaerobic rod, is one of the marker organisms that is now identified to be significant to the pathogenetic structure of biofilms associated with periodontal inflammation and should be considered an important organism for periodontal disease. Further, in comparison to the other traditional periodontal pathogens, F. alocis is present in the periodontal pocket in higher numbers and is least detected in healthy or periodontitis resistant patients. Currently, there is little or no information on the pathogenesis of F. alocis. In our laboratory, preliminary studies of F. alocis showed non-gingipain protease and sialidase activities. In silico analysis revealed molecular relatedness of several virulence factors from F. alocis and P. gingivalis. F. alocis was more resistant to oxidative stress and its growth stimulated under those condition in contrast to P. gingivalis. Biofilm formation was significantly increased in co-culture. There was an increase in adherence and invasion of epithelial cells in co-culture compared with P. gingivalis or F. alocis mono-cultures. In those epithelial cells, endocytic vesicle mediated internalization was only observed during co-culture. The F. alocis clinical isolate D-62D had an increased invasive capacity in co-culture with P. gingivalis compared to the F. alocis ATCC 35896 strain. In addition, there was variation in the proteome of the clinical isolates compared to the ATCC 35896 strain. Hypothetical proteins and those known to be important virulence factors in other bacteria were indentified. Our observations, taken together, may suggest that F. alocis has virulence properties that may enhance its ability to survive/persist in the periodontal pocket and may play an important role in infection-induced periodontal disease. It is our hypothesis that in F. alocis, similar to other periodontal pathogens, multiple coordinately regulated mechanisms are significant in the pathogenicity of the organism. We wish to gain an understanding of F. alocis potential virulence factors and evaluate whether they contribute to its pathogenicity. The primary goal of this R21 application is to develop a genetic system and an animal model to evaluate the host response to and virulence potential of F. alocis. The specific aims are: (1) To evaluate the specific role(s) of protease activity in the survival/pathogenicity of F. alocis. (2) o develop an animal model for testing the virulence potential of F. alocis. Collectively, the results from this study will establish basic information on the pathogenesis of F. alocis. It will generatea model system(s) that will yield important clues that will facilitate the development of novel therapeutic interventions to aid in the control and prevention of periodontal disease

描述（由申请人提供）：牙周袋中的细菌可以形成复杂的固着群落，在感染引起的牙周病中发挥重要作用。口腔微生物组项目中出现的数据正在促进范式的转变， 感染引起的牙周病。牙龈卟啉单胞菌、中间普雷沃菌、伴放线放线杆菌、嗜酸坦那菌和齿垢密螺旋体等细菌已被证明是牙周病的主要致病菌。然而，最近的发展，包括新的，文化的独立技术，允许识别尚未培养和挑剔的生物体在患者患有牙周炎。总的来说，这些研究表明牙周状况的变化与牙周袋中细菌群落组成的变化有关。Filifactoralocis，一种革兰氏阳性、溶砷、专性厌氧杆菌， 是目前被鉴定为对与牙周炎症相关的生物膜的致病结构具有重要意义的标志生物之一，并且应该被认为是牙周疾病的重要生物。此外，与其他传统的牙周致病菌相比，F。Alocis以较高的数量存在于牙周袋中，并且在健康或牙周炎抗性患者中检测到的最少。目前，关于F. alocis。本实验室对F. Alocis显示非牙龈卟啉菌蛋白酶和唾液酸酶活性。计算机模拟分析显示了几个毒力因子的分子相关性。alocis和牙龈卟啉单胞菌。F.与牙龈卟啉单胞菌相比，alocis对氧化应激更具抗性，并且在这些条件下其生长受到刺激。在共培养中，生物膜形成显著增加。与牙龈卟啉单胞菌或F.单种植物在这些上皮细胞中，内吞囊泡介导的内化仅在共培养期间观察到。食品药品管理alocis临床分离株D-62 D在与牙龈卟啉单胞菌共培养时的侵袭能力比F. alocis ATCC 35896菌株。此外，与ATCC 35896菌株相比，临床分离株的蛋白质组存在变异。鉴定了假设的蛋白质和那些已知在其他细菌中是重要毒力因子的蛋白质。我们的观察，综合起来，可能表明F。Alocis具有毒力特性，其可增强其在牙周袋中存活/持续的能力，并可在感染诱导的牙周病中发挥重要作用。这是我们的假设，在F。alocis与其他牙周致病菌相似，其致病机制是多个协同调节的。我们希望了解F。alocis潜在的毒力因子，并评估它们是否有助于其致病性。R21应用的主要目标是建立一个遗传系统和动物模型，以评估宿主对F. alocis。具体目的是：（1）研究蛋白酶活性在F. alocis。(2)建立一种动物模型，用于测试F. alocis。总的来说， 本研究将为F. alocis。它将产生一个模型系统，将产生重要的线索，将促进新的治疗干预措施的发展，以帮助控制和预防牙周病