B-306 Exploring transcriptional changes in mouse ocular tissue exposed to phosgene oxime

Abstract Background Phosgene oxime (CX), a toxic blistering and nettle agent, is an environmental toxicant. Injuries caused by CX extend beyond external organs, such as the eye, skin, and lungs, often impacting internal tissues due to its penetrative properties. Despite the eye’s vulnerability to toxic chemical agents, a research gap persists regarding changes in gene expression following ocular exposure to CX. Thus, this pilot study investigates the transcriptional changes underlying the toxicity of CX in mouse ocular tissue. Methods The eyeballs of C57Bl6 mice (6–8 weeks old, male and female, n=3) were exposed to CX for 30 seconds or underwent sham treatment, followed by enucleation 24 hours after exposure. mRNA was extracted using the phenol-chloroform method and sequenced by NovoGene on the Illumina NovaSeq PE150 platform. Sample quality and mRNA concentration were evaluated using the Agilent 2100 system. Differential gene expression analysis was performed using DESeq2 with a standard cutoff of p-value = 0.01 and |log2-Fold Change| = 1. Functional pathway enrichment was conducted using EnrichR, and selectively differentially expressed genes (DEGs) were validated through qPCR. Results Our findings revealed 697 downregulated and 233 upregulated genes following CX exposure. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis (p-value = 0.01) showed significant upregulation of pathways related to the inflammatory response and cell death in ocular tissues. Conclusion These results offer critical insights for studies aimed at finding effective treatments for phosgene oxime-induced ocular tissue injuries. Further analysis using single-cell transcriptomics and virtual therapeutic screening tools is necessary to identify biomarkers and clarify underlying molecular mechanisms.