Human Cytomegalovirus dysregulation of host hematopoietic progenitor cell signaling pathways to modulate latency, reactivation, and hematopoiesis during transplantation

总体项目摘要/摘要 我们的目标是阐明巨细胞病毒调节宿主信号的分子机制。 建立和维持病毒潜伏期和重新激活，并确定病毒如何失调 CD34造血祖细胞(HPC)信号转导可能影响造血功能。人巨细胞病毒仍然是 实体器官移植和造血干细胞术后发病率和死亡率的重要原因 细胞移植和骨髓抑制是人类巨细胞病毒感染的常见临床表现。 这些病人。在移植受者中，造血干细胞是潜伏的巨细胞病毒的关键储存库，因此提供了 传播到内脏器官的病毒来源。 使用CD34体外HPC模型和植入人胎骨的小鼠的初步数据 骨髓、肝脏和胸腺(huBLT小鼠)已表明HCMV对表皮生长因子的调节 CD34 HPC上的受体(EGFR)及其下游信号对病毒潜伏和重新激活是必不可少的，因为 以及造血术。我们的研究小组已经证明，在潜伏感染的CD34中有多个HCMV基因表达 包括UL133-138基因座、US28、UL7和HCMV miRNAs在内的HPC针对多个信号通路 由EGFR激活，以控制病毒潜伏/再激活和造血。我们假设HCMV罚款 调节EGFR及其下游途径的活性，以平衡病毒潜伏和重新激活的状态。我们 同时假设巨细胞病毒微调信号和细胞因子的分泌来影响造血。此外，我们 建议这一规定满足对抗性需求，促进传播，但限制广泛的造血 差异化以控制重新激活。 该计划项目将结合使用体外CD34 HPC模型来测试这些假设中的每一个 与huBLT小鼠模型和来自SOT和HSCT患者的样本进行比较。通知事件的复杂性 全面解决病毒潜伏和造血问题的方法只能是 通过PPG机制下的合作努力实现。因此，我们提出了五个高度整合的方案 研究项目(项目1：UL133/8调节宿主细胞信号在病毒潜伏和造血中的作用； 项目2：HCMV miRNA在病毒潜伏和造血中对宿主细胞信号的调节；项目3：HCMV US28病毒潜伏和造血中宿主细胞信号的调节；项目4：HCMV UL7调节 病毒潜伏和造血中的宿主细胞信号；项目5：HCMV对宿主细胞信号和 骨髓抑制中的细胞因子)，两个科学核心(人源化小鼠核心；基因组学，生物统计学和 生物信息学核心)来服务这些项目，以及一个行政核心来监督和协调整个 程序。

OVERALL PROJECT SUMMARY/ABSTRACT The goal of our program is to elucidate the molecular mechanisms of HCMV regulation of host signaling in the establishment and maintenance of viral latency and reactivation, and determine how viral dysregulation of CD34+ Hematopoietic Progenitor Cells (HPCs) signaling may compromise hematopoiesis. HCMV remains a significant cause of morbidity and mortality after Solid Organ Transplantation (SOT) and Hematopoietic Stem Cell Transplantation (HSCT), and myelosuppression is a common clinical manifestation of HCMV infection in these patients. HPCs represent a critical reservoir of latent HCMV in the transplant recipient, thereby providing a source of virus for dissemination to visceral organs. Preliminary data from our group using an in vitro CD34+ HPC model and mice engrafted with human fetal bone marrow, liver and thymus (huBLT mice) have shown that HCMV regulation of Epidermal Growth Factor Receptor (EGFR) and downstream signaling in CD34+ HPCs is essential for viral latency and reactivation as well as hematopoiesis. Our group has shown that multiple HCMV genes expressed in latently infected CD34+ HPCs including the UL133-138 locus, US28, UL7 and HCMV miRNAs target multiple signaling pathways activated by EGFR to control viral latency/reactivation and hematopoiesis. We hypothesize that HCMV fine tunes the activity of EGFR and its downstream pathways to balance states of viral latency and reactivation. We also hypothesize that HCMV fine tunes signaling and cytokine secretion to impact hematopoiesis. Further, we propose that this regulation meets antagonistic needs to promote dissemination but limit broad hematopoietic differentiation to control reactivation. This program project will test each of these hypotheses using the in vitro CD34+ HPC model in combination with the huBLT mouse model and samples from SOT and HSCT patients. The complexity of signaling events and approaches to comprehensively address questions on viral latency and hematopoiesis can only be achieved through a collaborative effort under a PPG mechanism. Therefore we propose five highly integrated research projects (Project 1: UL133/8 regulation of host cell signaling in viral latency and hematopoiesis; Project 2: HCMV miRNA regulation of host cell signaling in viral latency and hematopoiesis; Project 3: HCMV US28 regulation of host cell signaling in viral latency and hematopoiesis; Project 4: HCMV UL7 regulation of host cell signaling in viral latency and hematopoiesis; Project 5: HCMV regulation of host cell signaling and cytokines in myelosuppression), two scientific cores (Humanized Mouse Core; Genomics, Biostatistics and Bioinformatics Core) to service these projects, and an Administrative Core to oversee and coordinate the entire program.