P-3:Viral Chemokine signalling in HHV-8 infection

人类疱疹病毒-8（HHV-8，也称为KSHV）编码几种与以下疾病有关的蛋白质 病毒相关的发病机制。病毒性白细胞介素-6（vIL-6）和趋化因子受体（vGPCR）已经被发现。 由于它们的促有丝分裂和血管生成特性，它们促进肿瘤生长， 体外和体内实验系统，IL-6信号传导对卡波西肉瘤（KS）的增殖作用， 骨髓瘤和原发性渗出性淋巴瘤（PEL）细胞生长，以及vGPCR诱导KS样细胞增殖的能力。 在受体转导的小鼠中的疾病。然而，血管生成活性也受到每种趋化因子的影响， （vCCL-1，vCCL-2，vCCL-3），并且我们已经确定vCCL-1和vCCL-2特异性抗凋亡， 活性，如在用地塞米松攻击的HHV-8潜伏感染的PEL细胞中测量的，或 血清抽取这些活性，加上vCCL-2通过vGPCR调节信号传导的能力， 强烈表明V-趋化因子在裂解复制中起直接的自分泌作用。我们假设 这些病毒配体用于在裂解复制期间延长感染细胞的存活， 有利于病毒产生的细胞内条件。vCCL-1和vCCL-2的抗凋亡功能，如 它们的细胞对应物的类似活性尚未被详细研究，并且配体在 病毒生产性复制尚未被研究。此应用程序的目的是建立在我们的 先前关于v-趋化因子功能和vGPCR信号转导的工作，以研究vCCL的作用。 1和vCCL-2在裂解性复制中的作用以及vCCL-2：vGPCR相互作用与复制效率的相关性。 具体的目的是：（1）确定V-趋化因子抗凋亡信号传导的机制，（2）绘制 参与拮抗性vCCL-2：vGPCR相互作用的配体和受体残基，以及（3）确定 v-趋化因子在裂解性复制中的作用通过复制许可中的产生和利用 vCCL和vGPCR改变的HHV-8重组病毒的内皮细胞培养系统，和 通过使用核酶或siRNA在PEL细胞中的裂解再活化期间耗尽vCCL。这些数据 研究将描述V-趋化因子在病毒复制中的作用， 基于抗病毒vCCL-2的vGPCR拮抗剂的开发。

Human herpesvirus-8 (HHV-8, also called KSHV) encodes several proteins that have been implicated in virus-associated pathogenesis. The viral interleukin-6 (vlL-6) and chemokine receptor (vGPCR) have been studied extensively due to their mitogenic and angiogenic properties, their promotion of tumor growth in in vitro and in vivo experimental systems, the proliferative effects of IL-6 signalling on Kaposi's sarcoma (KS), myeloma and primary effusion lymphoma (PEL) cell growth, and the ability of vGPCR to induce KS-like disease in receptor-transduced mice. However, angiogenic activities are also effected by each of the vchemokines (vCCL-1, vCCL-2, vCCL-3), and we have determined that vCCL-1 and vCCL-2 specify antiapoptotic activities, as measured in HHV-8 latently-infected PEL cells challenged with dexamethasone or serum withdrawal. These activities, coupled with the ability of vCCL-2 to regulate the signalling by vGPCR, suggest strongly that the v-chemokines play direct, autocrine roles in lytic replication. We hypothesize that these viral ligands serve to prolong survival of infected cells during lytic replication and to promote intracellular conditions that favor virus production. The anti-apoptotic functions of vCCL-1 and vCCL-2, like similar activities of their cellular counterparts, have not been studied in detail, and the roles of the ligands in virus productive replication have not been investigated. The purpose of this application is to build on our previous work on v-chemokine function and vGPCR signal transduction to investigate the roles of the vCCL- 1 and vCCL-2 in lytic replication and the relevance of vCCL-2:vGPCR interactions to replication efficiency. The specific aims are: (1) to determine the mechanisms of v-chemokine anti-apoptotic signalling, (2) to map the ligand and receptor residues involved in antagonistic vCCL-2:vGPCR interactions, and (3) to determine the roles of the v-chemokines in lytic replication through the generation and utilization in replicationpermissive endothelial cell culture systems of vCCL- and vGPCR-altered HHV-8 recombinant viruses, and by using ribozymes or siRNAs to deplete vCCLs during lytic reactivation in PEL cells. The data from these studies will characterize the roles of the v-chemokines in virus replication and may provide the basis for the development of anti-viral vCCL-2-based vGPCR antagonists.