Investigation of enterovirus D68 pathogenesis in the human spinal cord

Megan Freeman，医学博士、哲学博士，匹兹堡大学儿科传染病 (ID) 研究员 医疗中心 (UPMC) 匹兹堡儿童医院 (CHP)。她在以下机构获得医学博士和博士学位： 她在范德比尔特大学研究了冠状病毒感染的细胞生物学和发病机制（Mark 丹尼森，医学博士）。在 CHP 接受儿科和儿科 ID 临床培训后，她加入了 Carolyn Coyne 的实验室， 博士，肠道病毒和病毒感染组织屏障方面的专家。她的研究重点是理解 肠道病毒 D68 (EV-D68) 发病机制，急性弛缓性脊髓炎 (AFM) 的假设病因，一种类似脊髓灰质炎的疾病 先前健康儿童的瘫痪综合症。弗里曼博士使用肠道类器官和初级 支气管上皮细胞表明一些与 AFM 相关的当代 EV-D68 分离株能够 除呼吸道外，还使用肠道进行复制，这表明存在另一种感染途径。 这项工作构成了本提案中脊髓类器官模型的基础。 Freeman 博士将以超过 10 年的病毒与宿主相互作用研究经验为基础，同时获得新的知识 精通免疫学、神经科学和成像技术，这将有助于她转变为 独立资助的儿科医生科学家。弗里曼博士汇集了多学科的指导和 顾问团队，由主要导师 John Williams 博士（呼吸道病毒免疫/发病机制）和共同主席担任主席 导师 Terence Dermody 博士（病毒发病机制/脑炎）。其他顾问成员包括博士。 Carolyn Coyne（肠道病毒/类器官）、Philana Lin 博士（免疫学）和 Clayton Wiley 博士 （神经科学/脑炎）。该委员会将促进技术获取、职业发展和 合作。培训计划包括课程作业、技术专长、书面和口头技能 沟通、负责任的研究行为、在会议上的演讲以及寻求的时间表 额外资金。匹兹堡大学医学院拥有出色的培养环境 记录科学成就、资源、对医师科学家的承诺和专业知识。 AFM 从 2012 年至 2018 年每两年达到一次峰值，与 EV-D68 流通同时发生，但原因如下 当代 EV-D68 的神经系统目标尚不清楚。该提案的中心假设是 现代EV-D68菌株直接感染脊髓运动神经元，导致神经元损伤 和瘫痪。使用创新的人类脊髓类器官模型，目标将 1) 定义脊髓 EV-D68 的复制，识别受感染的细胞类型，并发现对发病机制的贡献，2) 定义 脊髓类器官对 EV-D68 感染的宿主细胞反应，以及 3) 评估谷氨酸改变 EV-D68 感染脊髓类器官期间。本提案中的研究利用先进的组织 建模和成像技术、病毒复制测定以及宿主细胞因子、细胞死亡和 RNA 转录本分析以了解 EV-D68 的中枢神经系统感染如何导致 AFM。

Megan Freeman, MD, PhD, is a Pediatric Infectious Diseases (ID) Fellow at the University of Pittsburgh Medical Center (UPMC) Children’s Hospital of Pittsburgh (CHP). She earned MD and PhD degrees at Vanderbilt University where she investigated the cell biology and pathogenesis of coronavirus infection (Mark Denison, MD). After clinical training in Pediatrics and Pediatric ID at CHP, she joined the lab of Carolyn Coyne, PhD, an expert in enteroviruses and tissue barriers to viral infections. Her research focused on understanding enterovirus D68 (EV-D68) pathogenesis, the hypothesized cause of acute flaccid myelitis (AFM), a polio-like syndrome of paralysis in previously healthy children. Dr. Freeman used intestinal organoids and primary bronchial epithelial cells to show that some contemporary EV-D68 isolates associated with AFM were able to use the intestinal tract for replication in addition to the respiratory tract, suggesting an alternate infection route. This work formed the basis for the spinal cord organoid model featured in this proposal. Dr. Freeman will build on >10 years of experience studying viral-host interactions while gaining new proficiencies in immunology, neuroscience, and imaging techniques which will facilitate her transition into an independently-funded pediatrician-scientist. Dr. Freeman has assembled a multidisciplinary mentorship and advisory team, chaired by primary mentor Dr. John Williams (respiratory virus immunity/pathogenesis) and co- mentor Dr. Terence Dermody (viral pathogenesis/encephalitis). Additional advisory members include Dr. Carolyn Coyne (enteroviruses/organoids), Dr. Philana Lin (immunology) and Dr. Clayton Wiley (neuroscience/encephalitis). The committee will facilitate technique acquisition, career development, and collaborations. The training plan incorporates coursework, technical expertise, skills in written and oral communication, responsible conduct of research, presentation at conferences, and a timeline for seeking additional funding. The University of Pittsburgh School of Medicine is an outstanding training environment due to the record of scientific achievement, resources, commitment to physician scientists, and expertise. AFM peaked biennially from 2012-2018 coincident with EV-D68 circulation, however, reasons why contemporary EV-D68 targets the nervous system are unknown. The central hypothesis of this proposal is that contemporary strains of EV-D68 directly infect motor neurons of the spinal cord, resulting in neuronal damage and paralysis. Using an innovative human spinal cord organoid model, the Aims will 1) define spinal cord replication of EV-D68, identify infected cell type(s), and discover contributions to pathogenesis, 2) define the host cellular response of spinal cord organoids to infection with EV-D68, and 3) evaluate glutamate alterations during infection of spinal cord organoids with EV-D68. The studies in this proposal utilize advanced tissue modeling and imaging techniques, viral replication assays, as well as host cytokine, cellular death, and RNA transcript analysis to understand how CNS infection with EV-D68 leads to AFM.