Periodontal bacteria enhance oral KSHV pathogenesis and Kaposi's Sarcoma development in HIV + patients

项目摘要 卡波西肉瘤（KS）仍然是HIV/AIDS患者中最常见的肿瘤， 口腔是这种肿瘤最常见的临床表现之一。艾滋病毒感染会导致 增加患牙周病和口腔携带多种致病菌的风险。然而，在这方面， 牙周细菌和致癌病毒在局部环境中的相互作用是否有助于 这些病毒在口腔中的复制或维持在很大程度上仍然是未知的。我们的出版和 初步数据表明，人原代口腔细胞与两种原型病原体相关的 分子模式（PAMPs）产生的突出牙周细菌脂磷壁酸（LTA）从 金黄色葡萄球菌（Sa）和牙龈卟啉单胞菌（Pg）的脂多糖（LPS）-增加 初始病毒进入和随后在KSHV从头感染期间的潜伏基因表达。此外，长期协议和 LPS上调KSHV进入的细胞受体之一，硫酸乙酰肝素蛋白聚糖（HSPG）， 活性氧（ROS）的产生作为辅助因子有助于KSHV感染。另外，我们发现 来自Sa和Pg培养物的条件培养基或细菌PAMP诱导病毒裂解再活化， 潜伏感染的口腔细胞通过调节病毒microRNA的表达，促进病毒传播。为 临床相关性，我们发现在我们的口腔中Sa，Pg和KSHV的感染和合并感染率很高， HIV+患者队列中，发现唾液ROS、宿主抗氧化因子和细菌 HIV+/KSHV+患者LTA/LPS水平明显高于HIV+/KSHV-患者。根据这些数据，我们假设， 牙周细菌或其PAMP可能促进KSHV的初始感染、复制和传播 在口腔中的HIV+患者通过多种宿主和病毒因素，最终促进口腔 KS开发。为了解决这一假设，我们提出了以下具体目标，包括临床 基础研究：1）确定宿主唾液抗氧化剂与临床相关性及相关性 因素、特定细菌携带/PAMPs水平和HIV+患者的KSHV口腔脱落。2)识别 牙周细菌或其PAMP促进KSHV初始感染和病毒裂解的机制 重新激活是知识共享发展的两个重要步骤。通过这些努力，我们可以更好地 了解病原体合并感染如何促进口腔独特生态位中病毒相关癌症的发展 免疫功能低下的病人。我们的研究结果也将为临床开发提供框架 评价干扰宿主-细菌-病毒相互作用策略的试验（例如，特异性抗生素、靶向 TLRs-ROS轴或病毒microRNA合成），以评价其减少或预防口腔KSHV感染的能力， HIV+患者的KS进展。

PROJECT ABSTRACT Kaposi's sarcoma (KS) remains the most common tumor arising in patients with HIV/AIDS, and involvement of the oral cavity represents one of the most common clinical manifestations of this tumor. HIV infection incurs an increased risk for periodontal diseases and oral carriage from a variety of pathogenic bacteria. However, whether interactions involving periodontal bacteria and oncogenic viruses in the local environment facilitate replication or maintenance of these viruses in the oral cavity remains largely unknown. Our published and preliminary data indicate that incubation of human primary oral cells with two prototypical pathogen-associated molecular patterns (PAMPs) produced by prominent periodontal bacteria—lipoteichoic acid (LTA) from Staphylococcus aureus (Sa) and lipopolysaccharide (LPS) from Porphyromonas gingivalis (Pg)—increases initial viral entry and subsequent latent gene expression during de novo KSHV infection. Moreover, LTA and LPS up-regulate one of cellular receptors for KSHV entry, Heparan sulfate proteoglycan (HSPG) and increase reactive oxygen species (ROS) production as co-factor contributed to KSHV infection. Additionally, we found that conditioned medium from Sa and Pg culture or bacterial PAMPs induced viral lytic reactivation from latently infected oral cells through regulation of viral microRNAs expression, promoting virus dissemination. For clinical relevance, we found a high infection and co-infection rate of Sa, Pg and KSHV in the oral cavity of our cohort of HIV+ patients, and found higher levels of salivary ROS, host antioxidant factors and bacterial LTA/LPS from HIV+/KSHV+ patients than those HIV+/KSHV- ones. Based on these data, we hypothesize that periodontal bacteria or their PAMPs may facilitate initial KSHV infection, replication and dissemination in the oral cavity of HIV+ patients through multiple host and viral factors, and ultimately promote oral KS development. To address this hypothesis, we propose the following specific aims including both clinical and basic studies: 1) Determine the clinical relevance and correlations between host salivary antioxidant factors, specific bacterial carriage/PAMPs levels, and KSHV oral shedding in HIV+ patients. 2) Identify the mechanisms through which periodontal bacteria or their PAMPs facilitate KSHV initial infection and viral lytic reactivation, two important steps necessary for KS development. Through these efforts, we can better understand how pathogens co-infection can promote virus-associated cancer development in oral unique niche of immunocompromised patients. Our results will also provide the framework for the development of clinical trials evaluating the strategies interfering with host-bacteria-virus interaction (e.g. specific antibiotics, targeting TLRs-ROS axis or viral microRNAs synthesis) for their abilities to reduce or prevent oral KSHV infection and KS progression in HIV+ patients.