The pathogenesis of lung hypoplasia in congenital diaphragmatic hernia (CDH), a common birth defect, is poorly understood. The diaphragmatic defect can be repaired surgically, but the abnormal lung development contributes to a high mortality in these patients. To understand the underlying pathobiology, we compared the proteomic profiles of fetal rat lungs at the alveolar stage (E21) that were either exposed to nitrofen in utero (CDH lungs, n=5) or exposed to vehicle only (non-CDH control lungs, n=5). Pathway analysis of proteomic datasets showed significant enrichment in inflammatory response proteins associated with cytokine signaling and Epstein Barr Virus in nitrofen CDH lungs. Amongst the 218 significantly altered proteins between CDH and non-CDH control lungs were Tenascin C, CREBBP, LYN and STAT3. We showed that Tenascin C was decreased around the distal airway branches in nitrofen rat lungs and human CDH lungs, obtained from stillborn fetuses that did not receive pre- or postnatal treatment. In contrast, STAT3 was significantly increased in the airway epithelium of nitrofen lungs at E21. STAT3 inhibition after direct nitrofen exposure to fetal rat lung explants (E14.5) partially rescued the hypoplastic lung phenotype ex vivo by increasing peripheral lung budding. Moreover, we demonstrated that several STAT3 associated cytokines (IL-15, IL-9, IL-2) are increased in fetal tracheal aspirates of CDH survivors compared to non-survivors after fetoscopic endoluminal tracheal occlusion. With our unbiased proteomics approach, we showed for the first time that downstream inflammatory processes are likely involved in the pathogenesis of abnormal lung development in CDH.

先天性膈疝（CDH）是一种常见的出生缺陷，其肺发育不全的发病机制尚不清楚。膈肌缺损可以通过手术修复，但肺部发育异常导致这些患者的高死亡率。为了了解潜在的病理生物学，我们比较了在子宫内暴露于除草醚的胎鼠肺的肺泡阶段（E21）的蛋白质组谱。（CDH 肺，n=5）或仅暴露于媒介物（非 CDH 对照肺，n=5）。蛋白质组数据集的通路分析显示，除草醚 CDH 肺部中与细胞因子信号传导和 Epstein Barr 病毒相关的炎症反应蛋白显着富集。CDH 和非 CDH 对照肺之间 218 个显着改变的蛋白质包括 Tenascin C、CREBBP、LYN 和 STAT3。我们发现，从未接受产前或产后治疗的死产胎儿中获得的除草醚大鼠肺和人 CDH 肺中，远端气道分支周围的腱蛋白 C 减少。相反，在E21时，除草醚肺的气道上皮中的STAT3显着增加。直接将硝基苯暴露于胎鼠肺外植体 (E14.5) 后，STAT3 抑制可部分挽救离体发育不良的肺表型通过增加周围肺出芽。此外，我们证明，在胎儿镜腔内气管闭塞后，与非幸存者相比，CDH 幸存者的胎儿气管抽吸物中的几种 STAT3 相关细胞因子（IL-15、IL-9、IL-2）增加。通过我们公正的蛋白质组学方法，我们首次表明下游炎症过程可能参与 CDH 肺部发育异常的发病机制。