Functional screening for neutralizing antibodies targeting CMV entry factors

描述（由申请人提供）：人巨细胞病毒（CMV）是一种传染性疱疹病毒，在人群中血清患病率为60-90%，可导致免疫功能低下个体的发病率和死亡率。在免疫功能低下的宿主中发生的巨细胞病毒疾病的常见表现包括婴儿的神经元缺陷和胃肠道疾病、肺炎、巨细胞病毒综合征和移植受者的终末器官疾病。值得注意的是，巨细胞病毒是影响全球2.5%新生儿出生缺陷的主要原因，并与早期血管损伤有关，因为它可以感染内皮细胞和巨噬细胞。巨细胞病毒感染多种细胞类型（如内皮细胞、上皮细胞和单核细胞）的能力对于病毒在宿主内的传播和增殖至关重要。巨细胞病毒的进入需要病毒与细胞表面结合，结合后受体聚集，然后与细胞膜融合，释放细胞质中的衣壳。病毒融合事件可以发生在细胞表面，也可以在上皮细胞和内皮细胞的内体中以ph依赖的方式发生。尽管表皮生长因子受体和血小板衍生生长因子受体-¿与病毒进入有关，但CMV进入的给定复杂性将需要许多额外的细胞因子来确保病毒感染成功。我们假设独特的细胞表面蛋白在病毒结合、内吞、融合、转运到细胞核和病毒基因表达中发挥重要作用，是成功感染病毒所必需的。因此，我们计划利用最近开发的功能筛选中和抗体来发现对巨细胞病毒进入重要的上皮和内皮细胞因子。抗体靶点的鉴定和表征将揭示新的进入因子，并提供对病毒感染早期阶段的分子理解。此外，这些试剂将允许同时开发抗巨细胞病毒疗法，可用于限制巨细胞病毒相关疾病高危免疫受损患者的巨细胞病毒疾病。

DESCRIPTION (provided by applicant): Human cytomegalovirus (CMV) is a ¿-herpesvirus with a seroprevalance of 60-90% among the population that can cause morbidity and mortality in immuno-compromised individuals. Common manifestations of CMV disease that occur in immunocompromised hosts include neuronal defects in infants and gastrointestinal disorders, pneumonia, CMV syndrome, and end-organ disease in transplant recipients. Remarkably, CMV is the leading cause of birth defects affecting up to 2.5% of newborns worldwide and is linked to early vascular damage because it can infect endothelial cells and macrophages. The ability of CMV to infect multiple cell types such as endothelial cells, epithelial cells, and monocytes is essential for viral dissemination and proliferation within the host. CMV entry requires viral binding to the cell surface, post-binding receptor clustering followed by viral fusion with cell membranes and release of capsid in the cytosol. The viral fusion event can occur at the cell surface as well as in a pH-dependent manner within endosomes of epithelial and endothelial cells. Even though the epidermal growth factor receptor and the platelet-derived growth factor receptor-¿ have been implicated in virus entry, the given complexity of CMV entry would require many additional cell factors to ensure a successful virus infection. We hypothesize that unique cell surface proteins are essential for a successful virus infection by playing important roles in virus binding, endocytosis, fusion, trafficking to nucleus, and viral gene expression. Thus, we plan to utilize a recently developed functional screen for neutralizing antibodies to discover epithelial and endothelial cell factors important for CMV entry. The identification and characterization of the antibody's target will uncover novel entry factors and provide a molecular understanding of the early phase of a virus infection. Also, these reagents will allow for the simultaneous development of anti-CMV therapeutics that can be used to limit CMV disease in immuno- compromised patient at high-risk for CMV-associated disorders.