Interactions of KSHV and endothelial cells

描述(由申请人提供)： 在高效抗逆转录病毒治疗广泛应用之前，卡波西肉瘤(KS)是我国艾滋病患者最常见的肿瘤。KS是目前非洲地区报告最常见的肿瘤。卡波西肉瘤相关疱疹病毒(KSHV，正式名称为人类疱疹病毒8型，HHV-8)是KS的重要病原体。在KS中，KSHV存在于梭形细胞中，梭形细胞是一种内皮来源的细胞，是KS的肿瘤细胞。KSHV还与原发性渗出性淋巴瘤(PEL)有关，PEL是一种B细胞淋巴增生性疾病。PEL细胞系已经建立，并被用于KSHV的许多研究。然而，KS是一种以内皮细胞为基础的肿瘤，因此研究内皮细胞中的KSHV也很重要。疱疹病毒的特征都是潜伏感染，即病毒在宿主的生命周期内保持，但不产生传染性颗粒，以及裂解感染，即病毒复制并裂解宿主细胞。有趣的是，KS显然需要裂解期和潜伏期感染才能形成和维持。由于裂解感染的细胞正在死亡，一定有旁分泌因子产生，作用于潜伏感染的细胞。我们建议通过研究裂解基因在潜伏感染内皮细胞中的作用来表征裂解基因表达在KS维持中的作用。我们已经建立了一个易于处理的系统来研究KSHV在内皮细胞中的作用，我们将研究KSHV基因在我们的内皮细胞系统中的表达和功能。我们将创造和纯化与信号转导相关的显著裂解基因缺失的重组KSHV分离物。随后的分析将确定这些基因在裂解性和潜伏性感染中的作用。我们将分析裂解感染期间的生长和信号传递能力，并分析这些裂解基因如何改变潜伏感染细胞的宿主转录。

DESCRIPTION (provided by applicant): Kaposi's Sarcoma (KS) was the most common tumor in Aids patients in this country before the wide spread use of highly active antiretroviral therapy. KS is currently the most commonly reported tumor in regions of Africa. Kaposi's Sarcoma-associated herpesvirus (KSHV, formally known as human herpesvirus 8, HHV-8) is an essential etiologic agent for KS. In KS, KSHV is found in the spindle cell, a cell of endothelial origin that is the tumor cell of KS. KSHV is also associated with primary effusion lymphoma (PEL), a B-cell lymphoproliferative disorder. PEL cell lines have been created and are used for many studies of KSHV. However, KS is an endothelial cell based neoplasm and thus it is important to study KSHV in endothelial cells as well. Herpesviruses are all characterized by having latent infection, where the virus is maintained for the life of the host but does not produce infectious particles, and lytic infection, where the virus replicates and lyses the host cell. Interestingly, KS apparently requires both lytic and latent phase infection for formation and maintenance. Since the lytically infected cell is dying, there must be paracrine factors produced that act on latently infected cells. We propose to characterize the function of lytic gene expression in maintenance of KS by studying the role of lytic genes in latently infected endothelial cells. We have created a tractable system for studying KSHV in endothelial cells and we will study KSHV gene expression and function in our endothelial cell system. We will create and purify recombinant KSHV isolates deleted in prominent lytic genes involved in signal transduction. Subsequent analysis will characterize the role of these genes in both lytic and latent infection. We will analyze growth and signaling capabilities during lytic infection and we will analyze how these lytic genes alter host transcription in latently infected cells.