Transcriptomic analysis of of SNX-5422-treated human primary tracheobronchial epithelial (TBE) cells.

Purpose: In addition to developing antivirals targeting specific SARS-CoV-2 viral proteins, there has been a growing effort in developing therapeutics targeting host proteins exploited by SARS-CoV-2 for their replication or implicated in viral pathogenesis. As such therapeutics can impair normal functioning of host proteins, a clear understanding of their impact on cellular mechanisms is critically important. Here, we characterized the interactions of a host-targeted anti-SARS-CoV-2 therapeutic, SNX-5422, with the cellular machinery using a physiologically relevant ex vivo human primary tracheobronchial epithelial (TBE) cell model. Methods: Fully differentiated human TBE cells (EpiAirwayTM) from 3 independent donors with no reported respiratory disease or smoking history were obtained from MatTek (Ashland, MA). The cells were cultured at the air-liquid interface in 1 ml of AIR-100-MM culture medium (MatTek) in 6 well plates at 37°C in 5% CO2. Upon receipt of cells, the cultures were acclimated for 16-24hr prior to the start of experiments. Human TBE cells from each donor were treated with 1µM SNX-5422 or 0.1% DMSO added to the media on the basolateral side of the culture, in three biological replicates. After 48hrs, cells were resuspended in TRIzol reagent (Thermo Fisher) and total RNA from the cells was extracted by phase separation with chloroform and subsequently using the RNeasy Mini Kit (Qiagen). RNA-Seq libraries were prepared using TruSeq RNA library Prep Kit v2 (Illumina, Inc. USA). Before pooling and sequencing, fragment length distribution and library quality were assessed on a TapeStation 2200 (Agilent Technologies), and the libraries were validated by Qubit Fluorometers (Thermo Fisher). All libraries were then pooled in a concentration at 4nM and sequenced in quadruplets on a NextSeq 500 Illumina sequencing platform system using NextSeq 500/550 High Output Kit v2.0 (150 cycles) (Illumina, Inc. USA). Conclusion: This study identified differentially expressed genes between DMSO-treated and SNX-5422-treated human TBE cells. Overall design: Bulk RNA-seq analysis of human TBE cells from 3 independent donors with no reported respiratory disease or smoking history treated with 1µM SNX-5422 or 0.1%DMSO (drug-vehicle)