Multi-center Evaluation of the Threat of Established and Emerging Respiratory Viral Infections in Pediatric Transplant Recipients

儿科移植受者中已发生和新出现的呼吸道病毒感染威胁的多中心评估

• 批准号: 10540605
• 负责人: JANET A ENGLUND
• 金额: $ 67.6万
• 依托单位: ARKANSAS CHILDREN'S HOSPITAL RES INST
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-17 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10540605
• 关键词: Multi; center; Evaluation; Threat; Established

Respiratory viral infections (RVI) have changed the world. RVI are a leading cause of infectious morbidity and mortality in children undergoing hematopoietic cell transplantation (HCT) and solid organ transplantation (SOT). RVI diagnosis by qualitative PCR screening is sensitive, but unfortunately does not distinguish disease from presence of viral nucleic acid or predict risk for progression from upper to the more severe lower respiratory tract disease (LRTD). In the COVID-19 era, many centers now use pre-transplant RVI screening, but the implications of detection in an asymptomatic host are unknown. Integrating quantitative viral load, viral sequencing, and/or host immune (T cell and antibody) responses could provide novel predictive tools to stratify the risk of developing an RVI and the progression to LRTD. Our objective is to establish a comprehensive RVI diagnostic and disease progression predictive model in children undergoing transplantation. We propose a prospective multi-center epidemiologic study of 2000 pediatric transplant recipients, with a nested case-control immunologic and virologic substudy. This will be the largest study on RVI in any age group of HCT and SOT recipients. We will leverage the Pediatric Transplant ID Network (PIDTRAN), a consortium of 21 nationwide sites and the only group dedicated to pediatric transplant infectious diseases. We will obtain pre-transplant blood and nasal samples in all 2000 transplant participants at enrollment and also blood at day +100 post-transplant. In Aim 1, we will determine the prevalence of viral nucleic assay positivity using qualitative PCR and then perform quantitative PCR (qPCR) and viral sequencing (metagenomics) on positive specimens. We hypothesize that the quantity of respiratory viral nucleic acid or certain viral genotypes will identify patients at risk for progressive RVI. In Aim 2, we will develop an immunological classifier to predict risk of RVI and progression to LRTD using a nested substudy focused on three major pediatric viruses: RSV, parainfluenza virus 3, and human metapneumovirus. We will characterize pre-transplant humoral and cellular immune responses in the subset of patients who develop those RVIs compared with pre-transplant immunologic and day +100 post-transplant immune responses from uninfected matched controls. The combination of host response and virologic data (qPCR and viral metagenomics) will also be compared between RVI cases who do or do not progress to LRTD to identify biomarkers. We hypothesize that patients with specific functional antibody response and/or specific T cell repertoires to RVI will have superior clinical outcomes. Characterizing a comprehensive viral and host response pre-transplant, we will learn to predict who is at risk of LRTD and needs early intervention vs. delay of transplant, and when PCR positivity is indicative of live virus shedding and potential disease. These results will help formulate novel evidence-based pediatric guidelines for personalized clinical management of children undergoing transplant, and inform future antiviral and vaccine studies in these high-risk patient populations.

呼吸道病毒感染（RVI）改变了世界。 RVI 是传染性疾病发病的主要原因 接受造血细胞移植（HCT）和实体器官移植（SOT）的儿童死亡率。 通过定性 PCR 筛查进行的 RVI 诊断很敏感，但遗憾的是不能区分疾病和疾病 病毒核酸的存在或预测从上呼吸道进展到更严重的下呼吸道的风险 疾病（LRTD）。在 COVID-19 时代，许多中心现在使用移植前 RVI 筛查，但其影响 在无症状宿主中的检测结果尚不清楚。整合定量病毒载量、病毒测序和/或 宿主免疫（T 细胞和抗体）反应可以提供新的预测工具来分层发展风险 RVI 和 LRTD 的进展。我们的目标是建立全面的 RVI 诊断和疾病 接受移植的儿童的进展预测模型。我们提出了一个前瞻性的多中心 对 2000 名儿科移植受者进行的流行病学研究，采用巢式病例对照免疫学和病毒学研究 子研究。这将是针对 HCT 和 SOT 接受者任何年龄组的 RVI 的最大规模研究。我们将利用 儿科移植 ID 网络 (PIDTRAN)，一个由 21 个全国站点组成的联盟，也是唯一的组织 致力于小儿移植感染性疾病。我们将在以下时间获取移植前的血液和鼻腔样本 登记时所有 2000 名移植参与者以及移植后+100 天的血液。在目标 1 中，我们将 使用定性 PCR 确定病毒核酸检测阳性的发生率，然后进行定量 对阳性样本进行 PCR (qPCR) 和病毒测序（宏基因组学）。我们假设数量 呼吸道病毒核酸或某些病毒基因型将识别有进展性 RVI 风险的患者。在目标 2 中， 我们将开发一种免疫学分类器，使用嵌套模型来预测 RVI 和进展为 LRTD 的风险 亚组研究重点关注三种主要儿科病毒：RSV、副流感病毒 3 型和人类偏肺病毒。 我们将描述出现这种症状的患者亚组移植前体液和细胞免疫反应的特征 这些 RVI 与移植前免疫反应和移植后 +100 天的免疫反应进行比较 未感染的匹配对照。宿主反应和病毒学数据（qPCR 和病毒学数据）的结合 还将对进展或未进展为 LRTD 的 RVI 病例进行比较，以确定 生物标志物。我们假设具有特定功能性抗体反应和/或特定 T 细胞的患者 RVI 的全部方案将具有优异的临床结果。表征全面的病毒和宿主反应 移植前，我们将学习预测谁有 LRTD 风险并需要早期干预与延迟移植， PCR 阳性表明有活病毒脱落和潜在疾病。这些结果将有助于 制定新的循证儿科指南，以实现儿童的个性化临床管理 接受移植，并为这些高危患者群体未来的抗病毒和疫苗研究提供信息。