Innate immunity to Dengue Virus vaccine candidates in human ex vivo model systems

人类离体模型系统中对登革热病毒候选疫苗的先天免疫

• 批准号: 8909324
• 负责人: Rebecca E Hamlin
• 金额: $ 4.3万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8909324
• 关键词: 3' Untranslated Regions; Address; Adult; Animal Model; Antibody Response; Antiviral Agents; Attenuated; Biological Models; Blood; CD4 Positive T Lymphocytes; CXCL10 gene; Cell Cycle Kinetics; Cells; Clinical Trials; Coculture Techniques; Culicidae; Data; Death Rate; Dendritic Cells; Dengue; Dengue Virus; Disease; Equilibrium; Event; Flavivirus; Genes; Human; Immune; Immune response; Immunity; Infection; Interferon Type I; Interferons; Laboratories; Lead; Licensing; Life; Lymphoid Tissue; Macaca mulatta; Modeling; Molecular Profiling; Mutation; National Institute of Allergy and Infectious Disease; Natural Immunity; Nucleotides; Physiological; Production; Research; Risk; Sampling; Serotyping; Supportive care; System; T-Lymphocyte; Testing; Therapeutic; Tissue Model; Tissues; Tonsil; Tropism; Vaccination; Vaccines; Viral; Virus; Virus Diseases; adaptive immunity; base; chemokine; comparative; cytokine; human tissue; immunogenic; immunogenicity; immunoregulation; improved; monocyte; mutant; novel; pathogen; public health relevance; response; vaccination strategy; vaccine candidate; vector mosquito; virus host interaction

 DESCRIPTION (provided by applicant): Dengue Virus (DENV) is the most prevalent mosquito-borne virus causing disease in humans, with an estimated 2.5 billion people at risk of DENV infection, resulting in about 390 million annual infections worldwide. There are currently no licensed vaccines or specific therapeutics, and the death rate for severe dengue without proper supportive care can be over 20%. Candidate vaccines being developed by the NIAID utilize live, attenuated DENV strains with a 30 nucleotide deletion (rDENΔ30) in the 3' untranslated region (UTR). While viral replication and antibody responses to the NIAID DENV vaccine strains have been well studied in both rhesus macaques and humans, the innate and cellular immune responses remain largely uncharacterized. Based on our preliminary data with rDEN2Δ30, which show enhanced type I IFN responses in dendritic cells (DCs) and Th1 skewing of CD4+ T cells, we expect to observe differences regarding innate and cellular immune responses induced by WT DENV versus the NIAID vaccine candidates. Our central hypothesis is that the DENV vaccine strains with mutations in the 3' UTR will elicit enhanced host innate immune responses that may lead to more effective antiviral adaptive immune responses. The overall objective of this application is to characterize the cytokine expression profile produced by human DCs and the subsequent T cell priming that occurs in response to infection with NIAID vaccine strains compared to WT DENV strains. We will first address this in human primary cells since there is no reliable animal model that recapitulates dengue disease in humans. Next, we will validate these results in a newly developed, ex vivo human tonsil histoculture system to study DENV infection in the context of whole lymphoid tissue cytoarchitecture. In preliminary studies, we have demonstrated that human tonsil histocultures support a productive infection of WT DENV-2 and rDEN2Δ30 and support our initial findings in primary cells.

 描述（由申请人提供）：登革热病毒 (DENV) 是引起人类疾病的最流行的蚊媒病毒，估计有 25 亿人面临感染登革热病毒的风险，导致全球每年约 3.9 亿人感染。目前尚无获得许可的疫苗或特效疗法，如果没有适当的支持治疗，重症登革热的死亡率可能超过 20%。 NIAID 正在开发的候选疫苗利用活的减毒 DENV 毒株，该毒株在 3' 非翻译区 (UTR) 中有 30 个核苷酸缺失 (rDENΔ30)。虽然病毒复制和对 NIAID DENV 疫苗株的抗体反应已在恒河猴和人类中得到了充分研究，但先天免疫反应和细胞免疫反应在很大程度上仍然未知。 rDEN2Δ30 的初步数据显示树突状细胞 (DC) 中的 I 型 IFN 反应增强，并且 CD4+ T 细胞的 Th1 偏向，根据我们的初步数据，我们预计观察到 WT DENV 与 NIAID 候选疫苗诱导的先天和细胞免疫反应的差异。我们的中心假设是，3' UTR 突变的 DENV 疫苗株将引发增强的宿主先天免疫反应，从而可能导致更有效的抗病毒适应性免疫反应。本申请的总体目标是表征人类 DC 产生的细胞因子表达谱以及随后与 WT DENV 毒株相比响应 NIAID 疫苗株感染而发生的 T 细胞启动。我们将首先在人类原代细胞中解决这个问题，因为没有可靠的动物模型可以重现人类登革热疾病。接下来，我们将在新开发的离体人扁桃体组织培养系统中验证这些结果，以在整个淋巴组织细胞结构的背景下研究 DENV 感染。在初步研究中，我们已经证明人类扁桃体组织培养物支持 WT DENV-2 和 rDEN2Δ30 的高效感染，并支持我们在原代细胞中的初步发现。