Dengue Infected Endothelial Cells Enhance Immune Cell Activation

登革热感染的内皮细胞增强免疫细胞激活

• 批准号: 8385024
• 负责人: Erich R Mackow
• 金额: $ 19.63万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8385024
• 关键词: Address; Anaphylatoxins; Antibodies; Antibody Formation; Arteries; Autopsy; B-Lymphocytes; Blood; Blood Platelets; Blood Vessels; Blood capillaries; CXCL10 gene; CXCL11 gene; Capillary Permeability; Cell Degranulation; Cell Line; Cell Maturation; Cell Proliferation; Cell Surface Receptors; Cells; Chemotaxis; Complement; Complement 3a; Complement 5a; Complement Activation; Culicidae; Dendritic Cells; Dengue; Dengue Hemorrhagic Fever; Dengue Shock Syndrome; Dengue Virus; Disease; Disease model; Edema; Endothelial Cells; Endothelium; Extravasation; Figs - dietary; Hemorrhage; Human; Immune; Immune Cell Activation; Immune Targeting; Immune response; Immunoperoxidase Technics; In Vitro; Infection; Inflammation; Interleukin-7; Left; Leukocytes; Liquid substance; Liver; Lung; Mediating; Monitor; Mus; Natural Killer Cells; Pathogenesis; Pathway interactions; Patients; Peripheral; Peripheral Blood Lymphocyte; Permeability; Plasma; Play; Process; Production; Properdin; Proteins; RANTES; Recruitment Activity; Role; Sampling; Serotyping; Shock; Spleen; Staining method; Stains; Surface; T cell activating factor; T-Lymphocyte; Vascular Permeabilities; Viral; Viral Antigens; Viral Pathogenesis; Viremia; Virus; Virus Activation; Virus Diseases; capillary; chemokine; complement system; cytokine; in vivo; irofulven; mast cell; mortality; mouse model; neutrophil; release factor; response; virus pathogenesis

DESCRIPTION (provided by applicant): Dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are diseases caused by 4 serotypes of dengue virus (DV). Edema and hemorrhagic disease found in DHF/DSS result from vascular leakage, and these severe manifestations are enhanced by preexisting DV antibodies and subsequent infection by a second DV serotype. Thus an immune enhanced disease process contributes to increased endothelial cell (EC) permeability in DHF/DSS cases. DVs infect peripheral human leukocytes, dendritic cells and endothelial cells, and mechanisms by which DVs enhance vascular permeability are just beginning to be define. The ability of DVs to infect immune cells has resulted in many studies on infection of peripheral blood lymphocytes (PBLs) and their chemokine responses. Both are clearly important to viral pathogenesis and are readily studied in blood from humans or DV infected murine disease models. Although ECs are more difficult to study in vivo, they form the primary fluid barrier of the vasculature, and ultimately edema or hemorrhagic disease result from altering barrier functions of the endothelium. Postmortem studies of DV-infected patients and the AG129 mouse model demonstrate that ECs in the liver, lung, and spleen are infected. The ability of DVs to infect ECs provides a means for infection to alter capillary permeability, replicate and induce EC chemokine responses that activate and recruit immune cells to the endothelium. However, the contribution of DV infected ECs to immune enhancement and vascular permeability has yet to be factored into the DV disease process. DV infects ECs in culture, however prior in vitro studies were performed on ECs that were only 2-10% infected. In contrast, our recent studies of DV infected ECs were performed by synchronously infecting >80% of primary human ECs and monitoring viral and cellular responses. We found that DV productively infects primary human ECs, with a rapid increase in viral titer (~105/ml) 1 day p.i. Our findings suggest that DV infected ECs contribute to viremia, viral dissemination and the presentation of DV antigens on ECs that make them targets of antibodies and immune cells. Our analysis of EC responses to DV infection revealed the high level induction of chemokines that direct immune cell recruitment and activation. Cytokines CXCL10, CXCL11, IL-7, RANTES and BAFF are induced 337, 45, 128, 84 and 119 fold, respectively, in synchronously infected ECs by 24 hrs p.i. CXCL10/11 and RANTES secretion recruit and activate leukocytes and T-cells while IL-7 stimulates B, T and NK cell proliferation and T cell maturation. BAFF is a B and T cell activating factor that is released or expressed on the surface of activated ECs. DV infection also induced properdin (Factor P, 34-fold), which activates the alternative pathway (AP) complement system producing C3a/C5a: chemotactic anaphylatoxins which trigger localized inflammation, mast cell degranulation and vascular permeability. Importantly, high levels of C3a are present in severely ill dengue patients and associated with severe disease, plasma leakage and shock. These newly discovered EC responses indicate that ECs are not only targets of DV infection, but release factors that potentiate immune cell chemotaxis and permeability of the infected endothelium. Collectively these findings suggest that DV infected ECs contribute to viremia, enhanced immune responses and vascular permeability which are fundamental components of DHF and DSS. We propose to define EC responses to DV infection that enhance immune responses by activating and recruiting immune cells to the endothelium. PUBLIC HEALTH RELEVANCE: Dengue virus is carried by mosquitos and infects 50-100 million people/ year, causing a vascular leak disorder responsible for edema and hemorrhagic disease in 500,000-1,000,000/ year with a 5-30% mortality rate. Dengue results in an immune enhanced disease process whereby the 2nd infection is more severe from a distinct serotype. DV infects immune as well as endothelial cells that line capillaries and regulate edema and bleeding. We have found that DV infected endothelial cells elicit responses that enhance immune mediated responses that contribute to vascular leakage and contribute to increased virus production and spread. We address this process in endothelial cells in this study.

登革热（DF）、登革出血热（DHF）和登革休克综合征（DSS）是由4种血清型登革病毒（DV）引起的疾病。DHF/DSS患者的水肿和出血性疾病是由血管渗漏引起的，这些严重的症状会因先前存在的DV抗体和随后的第二种DV血清型感染而加重。因此，免疫增强的疾病过程有助于DHF/DSS病例中内皮细胞（EC）通透性的增加。DVs感染外周人白细胞、树突状细胞和内皮细胞，其增强血管通透性的机制刚刚开始被确定。DVs感染免疫细胞的能力导致了许多关于外周血淋巴细胞（pbl）感染及其趋化因子反应的研究。两者对病毒发病机制显然都很重要，并且很容易在人类或DV感染的小鼠疾病模型的血液中进行研究。尽管内皮细胞在体内的研究比较困难，但它们构成了脉管系统的主要液体屏障，内皮细胞屏障功能的改变最终导致水肿或出血性疾病。对dv感染患者和AG129小鼠模型的死后研究表明，肝脏、肺和脾脏的ECs受到感染。DVs感染内皮细胞的能力为感染提供了一种手段，可以改变毛细血管通透性，复制和诱导内皮细胞趋化因子反应，激活和招募免疫细胞到内皮细胞。然而，DV感染的内皮细胞对免疫增强和血管通透性的贡献尚未被考虑到DV疾病过程中。DV在培养物中感染ECs，但之前的体外研究仅对2-10%的ECs进行了感染。相比之下，我们最近对DV感染的ECs的研究是通过同步感染bb0 - 80%的原发性人ECs并监测病毒和细胞反应来进行的。我们发现，DV可有效感染原代人ECs，病毒滴度在1天内迅速增加（~105/ml）。我们的研究结果表明，DV感染的ECs有助于病毒血症、病毒传播和DV抗原在ECs上的呈递，使其成为抗体和免疫细胞的靶标。我们分析了EC对DV感染的反应，揭示了高水平诱导免疫细胞募集和激活的趋化因子。细胞因子CXCL10、CXCL11、IL-7、RANTES和BAFF在同步感染的ECs中分别被诱导337倍、45倍、128倍、84倍和119倍。CXCL10/11和RANTES的分泌招募和激活白细胞和T细胞，IL-7刺激B、T和NK细胞增殖和T细胞成熟。BAFF是一种B细胞和T细胞活化因子，在活化的内皮细胞表面释放或表达。DV感染还诱导properdin（因子P， 34倍），激活替代途径（AP）补体系统，产生C3a/C5a：趋化过敏毒素，引发局部炎症、肥大细胞脱颗粒和血管通透性。重要的是，重症登革热患者中存在高水平的C3a，并与严重疾病、血浆渗漏和休克相关。这些新发现的内皮细胞反应表明，内皮细胞不仅是DV感染的靶标，而且是增强免疫细胞趋化性和感染内皮通透性的释放因子。总的来说，这些发现表明DV感染的ECs会导致病毒血症，增强免疫反应和血管通透性，这些都是DHF和DSS的基本组成部分。我们建议定义EC对DV感染的反应，通过激活和招募免疫细胞到内皮细胞来增强免疫反应。