Human cytomegalovirus entry into epithelial and endothelial cells

人巨细胞病毒进入上皮细胞和内皮细胞

• 批准号: 8313972
• 负责人: David C. Johnson
• 金额: $ 43.69万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-07 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8313972
• 关键词: Acquired Immunodeficiency Syndrome; Affect; Benign; Binding; Biochemical; Cell fusion; Cell surface; Cells; Child; Clinical; Complex; Congenital Abnormality; Cytomegalovirus; Cytomegalovirus Infections; Defect; Development; Disease; Encephalitis; Endothelial Cells; Epithelial Cells; Epithelial Receptor Cell; Fibroblasts; Glycoproteins; Graft Rejection; Health; Hepatitis; Hepatocyte; Human; Immunocompromised Host; Infant; Infection; Intracellular Transport; Knowledge; Laboratory Study; Ligands; Mediating; Mediator of activation protein; Membrane; Membrane Fusion; Modeling; Molecular; Nervous system structure; Neuroglia; Neurons; Organ Transplantation; Pathogenesis; Patients; Pharmaceutical Preparations; Play; Pneumonia; Property; Proteins; Research; Retinal; Retinitis; Role; Syndrome; Testing; Time; Transplant Recipients; Tropism; Vaccine Design; Vaccines; Viral; Viral Proteins; Virion; Virus; Vulnerable Populations; cell type; cytomegalovirus glycoprotein gH; deafness; design; gastrointestinal; in utero; in vivo; macrophage; monocyte; novel; protein function; receptor; research study; vector; virus pathogenesis; virus tropism

DESCRIPTION (provided by applicant): Human cytomegalovirus (HCMV) is a ubiquitous, normally benign virus that establishes lifelong persistence and/or latency. However, infections in immunodeficient or immunosuppressed patients often cause severe disease including pneumonia, gastrointestinal syndromes, hepatitis, retinitis, and encephalitis. Importantly, HCMV frequently contributes to the rejection of transplanted organs. In immunologically naive children, HCMV can cause developmental defects of the CNS, especially deafness. Moreover, clinically recognized cases of HCMV in young children may represent only the "tip of the iceberg", many other infants with less well pronounced HCMV in utero may suffer more subtle developmental defects. HCMV causes a diverse spectrum of diseases, in part, related to a capacity to infect a broad array of cell types including epithelial, endothelial and glial cells, fibroblasts, monocyte-macrophages (M/M) and neurons. In order to infect all these different cell types, HCMV must bind onto cell surfaces and enter the cells. This fundamentally important first step in HCMV replication play an important role in virus tropism and pathogenesis, yet is poorly understood. In part, gaps in understanding HCMV entry, relate to the fact that extensively studied laboratory strains of HCMV fail to enter M/M, epithelial and endothelial cells. Clinical strains of HCMV enter all these diverse cell types, apparently because these viruses express two entry glycoproteins: gH/gL/UL128-131, required for entry into epithelial and endothelial cells and gH/gL/gO, required for entry into fibroblasts. Lab strains of HCMV (propagated long term on fibroblasts) express only gH/gL/gO. When we transduced epithelial cells to cause expression of gH/gL/UL128-131, HCMV entry into the cells was blocked. This "interference" with virus entry provides principal support for our hypothesis that gH/gL/UL128-131 functions to bind epithelial cell receptors. We are testing the related hypothesis that gH/gL/gO acts to bind fibroblast receptors. We also found that expression of gH/gL (without UL128-131) and a second HCMV glycoprotein, gB, caused fusion of epithelial cells, surprisingly, even when expressed in trans, i.e. gB in one set of cells and gH/gL in other cells. These observations have important conceptual implications for models of how viral proteins fuse membranes. Our ongoing research is focused on understanding how the two HCMV glycoproteins gH/gL/UL128-131 and gH/gL/gO are assembled and incorporated into virus particles, and how these proteins function in virus entry. Moreover, we will study the molecular mechanisms of gB and gH/gL-mediated membrane fusion. Other efforts will focus on the identification of novel cellular receptors that will explain clinical HCMV entry into epithelial and endothelial cells. Information about viral and cellular entry mediators is key to a better understanding of HCMV pathogenesis and for the design of vaccines and anti-virals. PUBLIC HEALTH RELEVANCE: Human cytomegalovirus (HCMV) causes substantial disease in several vulnerable populations: developing children, transplant patients, and AIDS patients. HCMV can infect a very broad spectrum of human cell types including retinal and gut epithelial cells, endothelial cells, hepatocytes, monocyte-macrophages and glial cells. Our studies will provide a better picture of how HCMV gains entry into biologically relevant epithelial and endothelial cells to facilitate the design of better anti-HCMV drugs and vaccines.

描述（由申请方提供）：人巨细胞病毒（HCMV）是一种普遍存在的正常良性病毒，可建立终身持续性和/或潜伏期。然而，免疫缺陷或免疫抑制患者的感染通常引起严重疾病，包括肺炎、胃肠道综合征、肝炎、视网膜炎和脑炎。重要的是，HCMV经常导致移植器官的排斥反应。在免疫幼稚儿童中，HCMV可引起CNS发育缺陷，尤其是耳聋。此外，临床上认可的幼儿HCMV病例可能仅代表“冰山一角”，许多其他子宫内HCMV不太明显的婴儿可能患有更微妙的发育缺陷。HCMV引起多种疾病，部分地与感染广泛的细胞类型的能力有关，所述细胞类型包括上皮细胞、内皮细胞和神经胶质细胞、成纤维细胞、单核细胞-巨噬细胞（M/M）和神经元。为了感染所有这些不同的细胞类型，HCMV必须结合到细胞表面并进入细胞。HCMV复制的第一步在病毒嗜性和发病机制中起着重要作用，但人们对此知之甚少。在某种程度上，理解HCMV进入的差距与以下事实有关：广泛研究的HCMV实验室菌株不能进入M/M、上皮细胞和内皮细胞。HCMV的临床株进入所有这些不同的细胞类型，显然是因为这些病毒表达两种进入糖蛋白：gH/gL/UL 128 -131，进入上皮和内皮细胞所需的，和gH/gL/gO，进入成纤维细胞所需的。HCMV的实验室菌株（在成纤维细胞上长期繁殖）仅表达gH/gL/gO。当我们转导上皮细胞以引起gH/gL/UL 128 -131的表达时，HCMV进入细胞被阻断。这种对病毒进入的“干扰”为我们的假设提供了主要支持，即gH/gL/UL 128 -131的功能是结合上皮细胞受体。我们正在检验gH/gL/gO结合成纤维细胞受体的相关假设。我们还发现，gH/gL（不含UL 128 -131）和第二种HCMV糖蛋白gB的表达引起上皮细胞的融合，令人惊讶的是，即使是在反式表达时，即gB在一组细胞中而gH/gL在其他细胞中。这些观察结果对病毒蛋白如何融合膜的模型具有重要的概念意义。我们正在进行的研究重点是了解两种HCMV糖蛋白gH/gL/UL 128 -131和gH/gL/gO是如何组装和整合到病毒颗粒中的，以及这些蛋白质在病毒进入中的功能。此外，我们将研究gB和gH/gL介导的膜融合的分子机制。其他的努力将集中在新的细胞受体，将解释临床HCMV进入上皮和内皮细胞的识别。关于病毒和细胞进入介质的信息是更好地理解HCMV发病机制和设计疫苗和抗病毒药物的关键。公共卫生相关性：人巨细胞病毒（HCMV）在几个脆弱人群中引起大量疾病：发育中的儿童，移植患者和艾滋病患者。HCMV可以感染非常广泛的人类细胞类型，包括视网膜和肠上皮细胞、内皮细胞、肝细胞、单核细胞-巨噬细胞和神经胶质细胞。我们的研究将提供一个更好的了解HCMV如何进入生物相关的上皮和内皮细胞，以促进更好的抗HCMV药物和疫苗的设计。