S1P as regulator of neonatal mucosal immune development and injury

总结 博士Rusconi对宿主微生物相互作用有着长期的兴趣。她的工作主要集中在婴儿出生 早产儿，特别容易出现危及生命的肠道相关病理，最明显的是坏死性 小肠结肠炎（NEC）。NEC的预防策略的缺乏及其糟糕的结果，迫使博士。 Rusconi对事件发生前的NEC标本进行广泛的代谢组学分析，以更好地了解其 病理生理学出现了独特的鞘脂谱，这在一个更大的队列中得到了证实， 质谱分析法来鞘脂在人体内发挥多种功能。鞘氨醇-1-磷酸 (S1P)是一种鞘脂代谢物，是促进淋巴细胞迁移的重要信号分子。的 S1 P受体1（S1 P1）对S1 P的感应在体内被多种S1 P1激动剂，如SEW 2871， 通过受体的内化和降解。通过用SEW 2871处理新生小鼠， 观察到预期的全身淋巴细胞减少和小肠树突状细胞和T细胞增加 固有层在成年小鼠中未观察到这些细胞在固有层中的蓄积。目标1将 重点是确定年龄特异性的小肠固有层对S1 P的功能反应 对抗Rusconi博士将用细胞类型特异性S1 P1 KO小鼠补充药理学数据， 细胞特异性要求。鞘脂特征和生态失调出现在相同的NEC前间隔。目的 二是确定关系。无菌小鼠将定植有微生态或对照早产儿。 微生物群，以评估对鞘脂的影响。目标1中使用的动物粪便内容物将用于确定 S1 P拮抗作用对微生物群的影响。最后，在目标3中，Rusconi博士将联合收割机S1 P1拮抗剂 和具有NEC样损伤模型的生态失调性早产儿微生物群。她将剖析积累的作用 淋巴细胞群和改变的微生物群对加重NEC样病变的影响。完成本提案 将提供S1 P信号传导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，这是NEC发生的生命间隔。具体地说， 这个K 01奖将使Rusconi博士能够提高她计划和进行动物实验的能力， 免疫学技能，并为她提供教学和实践培训，在赠款写作和手稿准备， 在一个高度指导的环境中。鲁斯科尼博士所在的研究所正在用一个初级教员来支持她的努力 任命，空间和保护时间来执行这项工作。她的顾问委员会由她的主要成员组成。 导师菲利普塔尔博士，共同导师罗德尼纽贝里博士和高塔姆丹塔斯，谁是研究人员与 在粘膜免疫、微生物-宿主相互作用、肠道疾病动物模型、 和人体微生物群建模。Rusconi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，这项K 01赠款将为鲁斯科尼博士提供 技能启动独立的研究生涯，融合生物信息学和实验生物学。

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.