Role of miR-181a-5p in Adenovirus 14p1 induced Acute Lung Injury

项目摘要 一种新的腺病毒（Ad）14，Ad 14 p1， 其诱导急性肺损伤，类似于在其它Ad血清型感染爆发期间观察到的急性肺损伤 (e.g., Ad 3、4和7）。然而，以前不可能进行比较病毒学和发病机理 研究，将原型、亲本Ad株（如Ad 14）与单一的、全球分布的遗传 例如Ad 14 p1。 这些Ad 14 p1感染严重程度增加的原因尚不清楚。我们已经证明 细胞感染Ad 14后发生细胞病变（CPE），引起免疫抑制反应 通过抑制IL-1b、IL-6、IL-8和TNF-α来激活人肺泡巨噬细胞。Ad14p1 CPE尸体增强了这些相同细胞因子的产生，这是由于CPE中病毒E1 B 20 K的表达减少。 Ad 14 p1 CPE尸体。与这些体外观察结果一致，用原型病毒感染叙利亚仓鼠， Ad 14导致最小的炎症和肺损伤，而Ad 14 p1感染诱导明显的急性肺损伤， 损伤和ARDS样病理学。 研究表明，凋亡细胞改变了microRNA（miRNA）的表达，这种表达可以抑制细胞凋亡。 研究人员发现，这些来自凋亡细胞的miRNA可以被递送到巨噬细胞。我们 假设类似的机制可能发生在Ad 14感染的细胞中，而不是感染Ad 14的细胞。 Ad 14 p1变体。为了验证这一点，我们用Ad 14或Ad 14 p1感染了人类细胞，并对细胞进行了小RNA测序。 各自的CPE尸体。数据显示，Ad 14 CPE尸体富含四种miRNA（Ad 14 miRNA）， 所有这些都显示出抑制促炎细胞因子的NF-kB依赖性转录， Ad 14 p1 CPE的尸体。我们的假设是这些特异性miRNA在Ad 14 CPE中的表达增加， 尸体及其转移到应答巨噬细胞是Ad 14 CPE尸体 抑制炎症反应。 我们在这里提出的研究将测试这些假设。我们将测试Ad 14 miRNA在调节细胞凋亡中的作用。 使用miRNA模拟物的巨噬细胞的炎症反应以及E1 B 20 K是否调节Ad 14 miRNA 感染时的表达。我们将测试最丰富表达的Ad 14 miRNA，miR-181 a-5 p， 作为Ad 14 CPE免疫表达的介导剂，通过使用3' UTR报告基因构建体和抑制miR-181 a-1， 5 P迷你拉链最后，我们将进行翻译研究，以确定miR-181 a-5 p在细胞凋亡中的作用。 Ad 14 p1感染叙利亚仓鼠的免疫发病机制。在这项工程完成后，我们预计 对病毒诱导的细胞miRNA在调节巨噬细胞中的作用有了更多的了解， 在急性肺损伤期间对Ad 14 p1的反应。我们的研究的积极影响将是 确定miRNA作为ARDS治疗干预的潜力。

PROJECT SUMMARY There have been globally distributed, regional outbreaks of a novel strain of adenovirus (Ad) 14, Ad14p1, that induces acute lung injury similar to that observed during outbreaks of infections with other Ad serotypes (e.g., Ad 3, 4 and 7). It has not, however, previously been possible to do comparative virology and pathogenesis studies, contrasting a prototype, parental Ad strain, such as Ad14, with a single, globally distributed genetic variant, such as Ad14p1. The reasons for the increased severity of these Ad14p1 infections are poorly defined. We have shown that cells undergoing Ad-induced cytopathic effect (CPE) from infection with Ad14 elicit an immunorepressive activity of activated human alveolar macrophages by repressing IL-1b, IL-6, IL-8 and TNF-alpha. In contrast, Ad14p1 CPE corpses enhance production of these same cytokines, due to decreased expression of viral E1B 20K in Ad14p1 CPE corpses. Consistent with these in vitro observations, infection of Syrian hamsters with prototype Ad14 resulted in minimal inflammation and lung injury, whereas Ad14p1 infection induced a marked acute lung injury and ARDS-like pathology. It has been shown that apoptotic cells have altered expression of microRNA (miRNA) that can repress pro- inflammatory responses and that these miRNA from apoptotic cells can be delivered to macrophages. We postulated that a similar mechanism could be occurring with Ad14 infected cells but not cells infected with the Ad14p1 variant. To test this, we infected human cells with Ad14 or Ad14p1 and did small RNA-seq on the respective CPE corpses. The data showed that Ad14 CPE corpses are enriched in four miRNA (Ad14 miRNA), all of which have been shown to repress NF-kB dependent transcription of pro-inflammatory cytokines, compared to Ad14p1 CPE corpses. Our hypothesis is that increased expression of these specific miRNA in Ad14 CPE corpses and their transfer to responder macrophages are the mechanisms through which Ad14 CPE corpses repress pro-inflammatory responses. The studies we propose here will test those hypotheses. We will test the role of Ad14 miRNA in modulating inflammatory responses of macrophages using miRNA mimics and whether E1B 20K modulates Ad14 miRNA expression during infection. We will test the role of the most abundantly expressed Ad14 miRNA, miR-181a-5p, as the mediator of Ad14 CPE immunorepression by using 3’ UTR reporter constructs and inhibiting miR-181a- 5p with miRZips. Finally, we will do translational studies to determine the role miR-181a-5p plays in the immunopathogenesis of Ad14p1 infection in the Syrian hamster. Upon completion of this project, we expect to have an increased understanding of the role of virally induced cellular miRNAs in modulation of macrophage responses during acute lung injury in response to Ad14p1. The positive impact of our studies will be the determination of the potential of miRNAs as therapeutic interventions for ARDS.