IMMUNOPATHOLOGICAL ANALYSIS OF DENGUE HEMORRHAGIC FEVER/DENGUE SHOCK SYNDROME

登革病毒感染是一个严重的发病率和死亡率的原因， 世界上的许多地区。 严重并发症的发病机制 登革病毒感染，登革出血热（DHF）是重要的， 为DHF的防治提供参考。 流行病学研究 已经表明DHF在继发性 感染不同血清型的登革热病毒， 原发性感染，并假设DHF是由 免疫病理机制 我们假设， 登革病毒-抗体复合物导致单核细胞显著活化 登革病毒特异性的CD 4+和CD 8 + T细胞和高表达的 导致DHF的细胞因子水平。 该项目的目标是确定免疫病理机制， 采用分子免疫学技术诱导DHF。 没有动物模型 可用于研究DHF;因此，使用人类受试者的研究 必需的. 我们将阐明免疫病理机制，通过分析 DHF患者外周血单个核细胞（PBMC）和血浆 或在急性期和之后患有无并发症的登革热（D） 复苏 我们将：1）确定CD 4+和CD 4+细胞中淋巴因子mRNA的水平， 体内活化的CD 8 + T细胞，2）确定登革病毒特异性 DHF患者的CD 4 =T细胞是Th 1或Th 2，通过建立CD 4 +T细胞， 克隆，3）确定登革病毒特异性CD 8 =T细胞克隆是否也 产生一组特征性的淋巴因子，以及4）分析T细胞受体 Valpha和Vbeta基因的使用，并确定T细胞活化是否是 体内寡克隆。 单核细胞是登革病毒复制最允许的人类细胞。 我们将测定患者单核细胞中细胞因子mRNA的水平， 用DHF或D. 此外，我们将确定传染性的水平 登革出血热患者血浆中的登革病毒抗体复合物。 的 D和DHF患者病毒分离株复制能力的比较 将在本项目中检测人单核细胞。 如果 如果检测到生长的显著差异，我们将以此作为 选择典型菌株进行基因组测序的生物标记物 项目3. 我们将定义体内的免疫反应， 在DHF中，基于对DHF或D. 这些分析将提供有关抗体的基本免疫学数据 和T细胞对登革病毒的反应，这是发展 安全有效的登革热疫苗。

Dengue virus infections are a serious cause of morbidity and mortality in many areas of the world. The pathogenesis of severe complications of dengue virus infection, dengue hemorrhagic fever (DHF) is important to elucidate for prevention and treatment of DHF. Epidemiological studies have shown that DHF is much more commonly observed during secondary infections with a different serotype of dengue virus from that which caused the primary infection, and it is assumed that DHF is caused by immunopathological mechanisms. We hypothesize that enhanced infection of monocytes by dengue virus-antibody complexes results in marked activation of dengue virus-specific CD4+ and CD8+ T cells and the production of high levels of cytokines which lead to DHF. The goal of this project is to define immunopathological mechanisms which induce DHF, using molecular immunological techniques. No animal models are available to study DHF; therefore, research using human subjects is required. We will elucidate immunopathological mechanisms by analyzing peripheral blood mononuclear cells (PBMC) and plasma of patients with DHF or with uncomplicated dengue fever (D) during the acute phase and after recovery. We will; 1) determine the levels of lymphokine mRNA in CD4+ and CD8+ T cells activated in vivo, 2) determine whether dengue virus-specific CD4=T cells in patients with DHF are Th1 or Th2 by establishing CD4+T cell clones, 3) determine whether dengue virus-specific CD8=T cell clones also produce a characteristic set of lymphokines, and 4) analyze T cell receptor Valpha and Vbeta gene usage and determine whether T cell activation is oligoclonal in vivo. Monocytes are the most permissive human cells for dengue virus replication. We will determine the levels of cytokine mRNA in monocytes from patients with DHF or D. Furthermore, we will determine the levels of infectious dengue virus-antibody complexes in the plasma of patients with DHF. The comparative ability of virus isolates from D and DHF patients to replicate in human monocytes will be tested in tested in this project. If significant differences in growth are detected, we will use this as a biologic marker for selecting typical strains for genome sequencing in project 3. We will define the immunological responses in vivo which result in DHF, based on these analyses of samples from patients with DHF or D. These analyses will provide basic immunological data concerning antibody and T cell responses to dengue virus that are needed for the development of safe and effective dengue vaccines.