KSHV interactions with host inflammasome components

KSHV 与宿主炎症小体成分的相互作用

• 批准号: 8731458
• 负责人: Bala Chandran
• 金额: $ 32.06万
• 依托单位: ROSALIND FRANKLIN UNIV OF MEDICINE & SCI
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-07 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8731458
• 关键词: Acetylation; Apoptosis; Area; B-Cell Lymphomas; B-Lymphocytes; Biological Assay; Bromodeoxyuridine; Caspase-1; Cell Line; Cell Nucleus; Cells; ChIP-on-chip; Chronic; Complex; Cytoplasm; DNA; DNA Binding; DNA Damage; DNA Viruses; Defense Mechanisms; Dermal; Disease; Elements; Endothelial Cells; Epstein-Barr Virus latency; Genome; Goals; HIV-1; Herpesviridae Infections; Herpesvirus 1; Histone H2B; Human; Human Herpesvirus 4; Human Herpesvirus 8; Immune response; Infection; Inflammation; Inflammatory; Inflammatory Response; Interferon Type II; Interferons; Interleukin-1; Interleukin-18; Kaposi Sarcoma; Knowledge; Label; Lead; Lesion; Ligation; Link; Lytic; Maintenance; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Microscopy; Modification; Molecular; Nuclear; Oral; Pathogenesis; Pathway interactions; Patients; Phase; Process; Proteins; Proteolytic Processing; Regulator Genes; Research; Reverse Transcriptase Polymerase Chain Reaction; Role; Site; Testing; Therapeutic; Time; Viral Proteins; cytokine; design; effusion; fast protein liquid chromatography; innovation; new technology; next generation sequencing; novel; pathogen; primary effusion lymphoma; procaspase-1; promoter; public health relevance; response; sensor; transcriptome sequencing

DESCRIPTION: KSHV is etiologically associated with chronic inflammation associated Kaposi's sarcoma (KS) and primary effusion B-cell lymphoma (PEL) in oral and other body sites that occur in HIV-1 infected patients. The inflammatory response is one of the key elements of KSHV pathogenesis. KS lesions are characterized by inflammatory cells and cytokines. The KS lesion endothelial cells and B-cell lines from PEL carry multiple copies of the KSHV genome in a latent state. Our long term goals are to elucidate KSHV's interactions with the host innate response during primary infection and latency, the pathways of cytokine induction and to define their role in KSHV pathogenesis. Our rationale is that such detailed knowledge is crucial for designing therapeutic strategies to control KSHV infection, inflammation and the associated malignancies. KSHV infected cells secrete multi-functional IL-1? and IL-18 cytokines into the supernatants. IL-1? and IL-18 are synthesized as inactive proIL-1? and proIL-18 and then undergo processing by activated caspase-1. However, caspase-1 itself is synthesized as a procaspase-1 and undergoes activation leading into an auto- proteolytic cleavage. Procaspase-1 activation is mediated by a molecular platform called an "inflammasome" that is formed by homotypic interactions of a sensor protein recognizing the danger trigger, an adaptor ASC molecule, and procaspase-1. Our studies have demonstrated that the pathogen sensing functions of the inflammasome also extends into the nucleus. During de novo KSHV infection of human microvascular dermal endothelial (HMVEC-d) cells, gamma-interferon-inducible protein (IFI16) is colocalized with the KSHV genome in the infected endothelial cell nucleus, and interacted with ASC and procaspase-1 to form an inflammasome complex. IFI16 also colocalized with the KSHV genome in the nuclei of latently infected endothelial and PEL cells, and only the IFI16 dependent inflammasome is constitutively activated in KSHV latently infected cells. Human KS and PEL lesions showed evidence of IFI16-ASC inflammasome activation. Constitutive induction of the IFI16-inflammasome was also observed in ?1-EBV latency I, II and III cells. Together with the ability of KSHV and EBV latency in the presence of the IFI16-inflammasome and association of IFI16 with KSHV and EBV genome in the latently infected cells, we hypothesize that "IFI16 is involved in the innate sensing of foreign episomal DNA in the nucleus and KSHV utilizes IFI16 for its latency". This hypothesis will be tested by three innovative and interlinked specific aims. These studies are significant since such elucidation wil lead into designing therapeutic strategies to control KSHV induced inflammation and the associated malignancies. These will also profoundly enhance the current concepts of innate sensing in the nucleus and will lead into new technologies and treatments that will benefit not only the KSHV area of research but also other fields.

描述：KSHV 在病因学上与 HIV-1 感染患者口腔和其他身体部位发生的卡波西肉瘤 (KS) 和原发性渗出性 B 细胞淋巴瘤 (PEL) 相关的慢性炎症有关。炎症反应是KSHV发病机制的关键要素之一。 KS 病变的特征是炎症细胞和细胞因子。来自 PEL 的 KS 病变内皮细胞和 B 细胞系携带多个处于潜伏状态的 KSHV 基因组拷贝。我们的长期目标是阐明 KSHV 在原发感染和潜伏期与宿主先天反应的相互作用、细胞因子诱导途径，并确定它们在 KSHV 发病机制中的作用。我们的理由是，这种详细的知识对于设计控制 KSHV 感染、炎症和相关恶性肿瘤的治疗策略至关重要。 KSHV感染细胞分泌多功能IL-1？和IL-18细胞因子进入上清液。白介素-1？和 IL-18 合成为无活性的 proIL-1？和 proIL-18，然后经过激活的 caspase-1 的处理。然而，caspase-1 本身被合成为 procaspase-1，并经历激活导致自蛋白水解裂解。 Procaspase-1 的激活是由称为“炎症小体”的分子平台介导的，该平台是由识别危险触发器的传感器蛋白、适配器 ASC 分子和 procaspase-1 的同型相互作用形成的。我们的研究表明，炎症小体的病原体感知功能也延伸到细胞核。在 KSHV 从头感染人微血管真皮内皮 (HMVEC-d) 细胞期间，γ-干扰素诱导蛋白 (IFI16) 与受感染内皮细胞核中的 KSHV 基因组共定位，并与 ASC 和 procaspase-1 相互作用形成炎性体复合物。 IFI16 还与 KSHV 基因组共定位于潜伏感染的内皮细胞和 PEL 细胞的细胞核中，并且只有 IFI16 依赖性炎症小体在 KSHV 潜伏感染的细胞中被组成型激活。人类 KS 和 PEL 病变显示 IFI16-ASC 炎性小体激活的证据。在 ?1-EBV 潜伏期 I、II 和 III 细胞中也观察到了 IFI16-炎症小体的组成型诱导。结合 IFI16 炎症体存在下 KSHV 和 EBV 潜伏的能力以及 IFI16 与潜伏感染细胞中 KSHV 和 EBV 基因组的关联，我们假设“IFI16 参与细胞核中外来游离 DNA 的先天感知，而 KSHV 利用 IFI16 进行潜伏”。这一假设将通过三个创新且相互关联的具体目标进行检验。 这些研究意义重大，因为此类阐明将导致设计治疗策略来控制 KSHV 引起的炎症和相关恶性肿瘤。这些还将深刻增强当前细胞核固有传感的概念，并将带来新技术和治疗方法，这不仅有利于 KSHV 研究领域，也有利于其他领域。