A novel zebrafish embryo model to define virulence factors of Bartonella henselae

一种新的斑马鱼胚胎模型来定义汉赛巴尔通体的毒力因子

• 批准号: 8911767
• 负责人: BURT E ANDERSON
• 金额: $ 18.69万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8911767
• 关键词: Address; Adherence; Adhesions; Agglutination; Amino Acids; Bacillary Angiomatosis; Bacteremia; Bacteria; Bacterial Adhesins; Bacterial Infections; Bartonella; Bartonella henselae; Binding; Blood Vessels; Blood capillaries; Breeding; Cat-Scratch Disease; Cells; Clinical; Collagen; Country; Developmental Biology; Disease; Embryo; Endocarditis; Endothelial Cells; Extracellular Matrix; Extracellular Matrix Proteins; Family; Genes; Goals; Health; Human; IL8 gene; Immune response; Immune system; Immunocompromised Host; In Vitro; Individual; Infection; Length; Lymphatic Diseases; Mediating; Modeling; Molecular Weight; Monitor; NF-kappa B; Nodule; Organ; Pathogenesis; Patients; Phagocytosis Induction; Play; Process; Protein Inhibition; Proteins; Regulation; Regulator Genes; Role; Skin; Structure; Surface; Symptoms; System; Systemic disease; Systemic infection; Testing; Transgenic Organisms; Type IV Secretion System Pathway; Vascular Endothelial Growth Factors; Vertebrates; Virulence; Virulence Factors; Yolk Sac; Zebrafish; angiogenesis; biological adaptation to stress; capillary; extracellular; genetic regulatory protein; in vivo; in vivo Model; nonhuman primate; novel; prevent; response; treatment strategy; Address; Adherence; Adhesions; Agglutination; Amino Acids; Bacillary Angiomatosis; Bacteremia; Bacteria; Bacterial Adhesins; Bacterial Infections; Bartonella; Bartonella henselae; Binding; Blood Vessels; Blood capillaries; Breeding; Cat-Scratch Disease; Cells; Clinical; Collagen; Country; Developmental Biology; Disease; Embryo; Endocarditis; Endothelial Cells; Extracellular Matrix; Extracellular Matrix Proteins; Family; Genes; Goals; Health; Human; IL8 gene; Immune response; Immune system; Immunocompromised Host; In Vitro; Individual; Infection; Length; Lymphatic Diseases; Mediating; Modeling; Molecular Weight; Monitor; NF-kappa B; Nodule; Organ; Pathogenesis; Patients; Phagocytosis Induction; Play; Process; Protein Inhibition; Proteins; Regulation; Regulator Genes; Role; Skin; Structure; Surface; Symptoms; System; Systemic disease; Systemic infection; Testing; Transgenic Organisms; Type IV Secretion System Pathway; Vascular Endothelial Growth Factors; Vertebrates; Virulence; Virulence Factors; Yolk Sac; Zebrafish; angiogenesis; biological adaptation to stress; capillary; extracellular; genetic regulatory protein; in vivo; in vivo Model; nonhuman primate; novel; prevent; response; treatment strategy

DESCRIPTION (provided by applicant): Infection of humans with the zoonotic bacterium Bartonella henselae (Bh) can result in a range of clinical symptoms and disease including lymphadenopathy associated with localized Bh infection observed in cat-scratch disease, to endocarditis and bacteremia resulting from systemic disease. In some patients, systemic infection with Bh includes bacillary angiomatosis which is characterized by red/purple nodules on the skin or internal organs due to proliferation of the small blood vessels. This unusual angiogenic host response to infection is unique among bacteria to certain Bartonella species. In vitro studies have defined important virulence factors in Bh that play a role in establishing infection and/or eliciting a host response. The first is the VirB/VirD4 type IV secretion system that is responsible for delivering the bartonella effector proteins (Beps A-G) that act on endothelial cells in varying capacities. The second major virulence factor is a VirB-independent second type IV secretion system Trw, which encodes multiple proteins including small adhesins TrwL1-TrwL-8 which have been shown to play an important role in host cell adherence. Lastly, the high molecular weight trimeric auto transporter adhesin BadA has been studied extensively in vitro and is critical for auto agglutination, adhesion to host cells, binding to extracellular mtrix proteins, inhibition of phagocytosis, and induction of angiogenesis. While in vitro studies have proven invaluable for the study of Bh pathogenesis, no Bh virulence factors have been confirmed in vivo and remarkably little is known about how the genes encoding these virulence factors are regulated. To address this problem, we have developed a novel in vivo model of Bh infection using transgenic zebra fish (ZF) embryos that permits us to both monitor infection and host response including angiogenesis. We hypothesize that our ZF embryo model will enable us to: more rigorously test the role of virulence factors that have been defined in vitro; identify ne virulence factors and regulators of virulence in vivo ; and assess the role of these gene products in the host response to Bh infection. To test these hypotheses we propose the following specific aims: 1) Define the role of virulence factors and regulators of virulence in Bh infection using the transgenic ZF embryo model, and 2) Determine the role of Bh virulence factors and regulatory proteins in eliciting a host response to infection in experimentally infected transgenic ZF embryos. An in vivo model is urgently needed to better understand the unique pathogenesis and host response to this bacterium in order to develop novel treatment strategies.

描述（由申请人提供）：人畜共患细菌的感染Bartonella henselae（BH）可导致一系列临床症状和疾病，包括与猫抓病中观察到的局部BH感染相关的淋巴结肿大，从而导致患有系统疾病的心内膜炎和细菌。在某些患者中，BH的全身感染包括细菌血管瘤病，其特征是由于小血管增殖，皮肤或内部器官上的红色/紫色结节。这种不寻常的血管生成宿主对感染的反应在细菌中对某些Bartonella物种是独一无二的。体外研究已定义了BH中重要的毒力因子，这些因子在建立感染和/或引发宿主反应中发挥作用。第一个是virb/vird4型IV分泌系统，该系统负责传递在不同能力的内皮细胞上作用于内皮细胞的Bartonella效应蛋白（BEPS A-G）。第二个主要的毒力因子是独立于VIRB的第二型IV分泌系统TRW，该系统编码多种蛋白质，包括小蛋白TRWL1-TRWL-8，已显示出在宿主细胞粘附中起重要作用。最后，已经对三聚体自动转运蛋白粘附蛋白BADA进行了广泛的研究，对自身凝集，宿主细胞的粘附，与细胞外MTRIX蛋白的结合，抑制吞噬细胞增多症和诱导血管生成至关重要。虽然在体外研究对BH发病机理的研究证明是无价的，但在体内尚未证实BH毒力因子，并且对于如何调节这些毒力因子的基因如何受到了解。为了解决这个问题，我们使用转基因斑马鱼（ZF）胚胎开发了一种新型的BH感染体内模型，该模型允许我们监测感染和宿主反应，包括血管生成。我们假设我们的ZF胚胎模型将使我们能够：更严格地测试在体外定义的毒力因子的作用；确定体内毒力的毒力因子和调节剂；并评估这些基因产物在宿主对BH感染的反应中的作用。为了检验这些假设，我们提出了以下特定目的：1）使用使用毒力因素和毒力调节剂在BH感染中的作用 转基因ZF胚胎模型和2）确定BH毒力因子和调节蛋白在引起实验感染的转基因ZF胚胎中感染的宿主反应中的作用。迫切需要一个体内模型，以更好地了解该细菌的独特发病机理和宿主反应，以制定新的治疗策略。