S1P as regulator of neonatal mucosal immune development and injury

摘要 鲁斯科尼博士长期以来一直对宿主微生物的相互作用感兴趣。她的工作重点是婴儿出生 早产儿，他们特别容易发生危及生命的肠道相关病理，最明显的是坏死性病变 小肠炎(NEC)。由于缺乏对NEC及其糟糕后果的预防战略，迫使Dr。 Rusconi将对事件前的NEC样本进行广泛的代谢组学分析，以更好地了解其 病理生理学。一种独特的鞘脂特征出现了，这在一个更大的队列中得到了靶标的证实 质谱学。鞘脂在人体内发挥着不同的功能。鞘氨醇-1-磷酸 鞘磷脂代谢产物(S1P)是促进淋巴细胞迁移的重要信号分子。这个 S1P受体1(S1P1)对S1P的感觉在体内被多种S1P1激动剂拮抗，如SEW2871， 通过受体的内化和降解。用SEW2871 SHE治疗新生小鼠 观察到预测的全身性淋巴细胞减少和小肠中树突状细胞和T细胞的增加 固有层。在成年小鼠的固有层中没有观察到这些细胞的聚集。目标1将 重点识别S1P时小肠固有层的年龄特异性功能反应 对抗性。Rusconi博士将用特定细胞类型的S1P1 KO小鼠补充药理学数据 特定于单元的要求。神经鞘脂信号和生物失调出现在NEC前的同一个时间间隔内。目标 2重点是确定他们之间的关系。无菌小鼠将被生态型早产或对照早产定植 微生物区系，以评估对鞘脂的影响。目标1中使用的动物的粪便内容将被用来确定 S1P拮抗对微生物区系的影响。最后，在目标3中，Rusconi博士将结合S1P1拮抗剂 以及具有NEC样损伤模型的早产微生物区系。她将剖析积累的作用 淋巴细胞群和改变的微生物区系对加重NEC样病变的作用。完成本建议书 将提供关于S1P信号在粘膜免疫建立中的作用及其 与成熟肠道中的微生物群相互作用，在此期间NEC发生。具体来说， 这一K01奖项将允许Rusconi博士提高她计划和进行动物实验的能力，完善她的 免疫学技能，并为她提供赠款撰写和手稿准备方面的说教和实践培训， 在一个高度指导的环境中。鲁斯科尼博士的研究所正在用一名初级教员支持她的努力 执行这项工作的预约、空间和保护时间。她的顾问委员会由她的初选组成 导师Phillip Tarr博士、共同导师Rodney Newberry博士和Gautam Dantas博士，他们是 在粘膜免疫、微生物-宿主相互作用、肠道疾病动物模型、 和人类微生物区系建模。鲁斯科尼博士的职业发展计划增加了她在生物化学方面的培训， 分子生物学、微生物学和生物信息学。总之，这笔K01拨款将为Rusconi博士提供 将生物信息学和实验生物学结合起来，开始独立研究事业的技能。

SUMMARY Dr. Rusconi has a long-standing interest in host microbial interactions. Her work has focused on infants born preterm, who are exceptionally prone to life-threatening gut-associated pathology, most notably necrotizing enterocolitis (NEC). The absence of preventive strategies for NEC and its abysmal outcomes, compelled Dr. Rusconi to perform a broad range metabolomics analysis of pre-event NEC specimens to better understand its pathophysiology. A unique sphingolipid profile emerged, which was confirmed in a larger cohort by targeted mass spectrometry. Sphingolipids perform diverse functions in the human body. Sphingosine-1-phosphate (S1P), a sphingolipid metabolite, is an important signaling molecule that promotes lymphocyte migration. The sensing of S1P by S1P receptor 1 (S1P1) is antagonized in vivo by multiple S1P1 agonists, such as SEW2871, through the internalization and degradation of the receptor. By treating neonatal mice with SEW2871 she observed the predicted systemic lymphopenia and and increase in dendritic and T cells in the small intestine lamina propria. The accumulation of these cells in the lamina propria was not observed in adult mice. Aim 1 will focus on identifying age-specific functional responses of the small intestinal lamina propria upon S1P antagonism. Dr. Rusconi will complement pharmacological data with cell-type specific S1P1 KO mice to address cell-specific requirements. The sphingolipid signature and dysbiosis appear in the same pre-NEC interval. Aim 2 focuses on determining their relationship. Germ-free mice will be colonized with dysbiotic or control preterm microbiota to assess impact on sphingolipids. Fecal content from animals used in Aim 1 will be used to determine the impact of S1P antagonism on the microbiota. Finally, in Aim 3, Dr. Rusconi will combine S1P1 antagonism and dysbiotic preterm microbiota with the NEC-like injury model. She will dissect the role of accumulating lymphocyte populations and altered microbiota on exacerbating NEC-like lesions. Completion of this proposal will provide much needed information on the role of S1P signaling in mucosal immunity establishment and its interplay with the microbiota in the maturing intestine, an interval of life during which NEC occurs. Specifically, this K01 award will allow Dr. Rusconi to improve her ability to plan and conduct animal experiments, refine her immunology skills, and provide her with didactic and practical training in grant writing and manuscript preparation, in a highly mentored environment. Dr. Rusconi’s Institution is supporting her effort with a junior faculty appointment, space, and protected time to perform this work. Her advisory committee consists of her primary mentor Dr. Phillip Tarr, co-mentors Drs. Rodney Newberry and Gautam Dantas, who are investigators with complementary expertise in mucosal immunity, microbe-host interactions, animal models of intestinal disease, and human microbiota modeling. Dr. Rusconi’s Career Development Plan adds to her training in biochemistry, molecular biology, microbiology, and bioinformatics. In summary, this K01 grant will provide Dr. Rusconi the skills to launch an independent research career, amalgamating bioinformatics and experimental biology.