RNA Sequencing Analysis of Monocytes Exposed to Airway Fluid from Children with Pediatric Acute Respiratory Distress Syndrome

Objectives: To identify differentially expressed genes and networks using a novel transcriptomic reporter assay with donor monocytes exposed to the airway fluid of intubated children with and at-risk for PARDS. To determine differences in gene expression at two time points using the donor monocyte assay exposed to airway fluid from intubated children with PARDS obtained 48-96 hours following initial tracheal aspirate sampling. Design, Setting and Participants: In vitro pilot study carried out using airway fluid supernatant from 57 children: 44 children with PARDS and 13 children at-risk for PARDS. Main Outcomes and Measures: We performed bulk RNA sequencing using a transcriptomic reporter assay of monocytes exposed to airway fluid from intubated children to discover gene networks differentiating PARDS from at-risk for PARDS. We also report differences in gene expression in children with PARDS 48-96 hours following initial tracheal aspirate sampling. Results: We found that interleukin (IL)-10, -4, and -13, cytokine/chemokine signaling, and the senescence-associated secretory phenotype are upregulated in monocytes exposed to airway fluid from intubated children with PARDS compared to those at-risk for PARDS. Signaling by NOTCH, histone deacetylation/acetylation, DNA methylation, chromatin modifications (B-WICH complex), and RNA polymerase I transcription and its associated regulatory apparatus were upregulation in children with PARDS 48-96 hours following initial tracheal aspirate sampling. Conclusions and Relevance: We identified gene networks important to the PARDS airway immune response using bulk RNA sequencing from a monocyte reporter assay that exposed monocytes to airway fluid from intubated children with and at-risk for PARDS. Mechanistic investigations are needed to validate our findings.