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bioRxiv · 10.1101/2024.12.03.626720

Contact Lens Wear Alters Transcriptional Responses to Pseudomonas aeruginosa in Both the Corneal Epithelium and the Bacteria

Abstract

PurposeHealthy corneas resist colonization by virtually all microbes yet contact lens wear can predispose the cornea to sight-threatening infection with Pseudomonas aeruginosa. Here, we explored how lens wear changes corneal epithelium transcriptional responses to P. aeruginosa and its impact on bacterial gene expression. MethodsMale and female C57BL/6J mice were fitted with a contact lens on one eye for 24 h. After lens removal, corneas were immediately challenged for 4 h with P. aeruginosa. A separate group of naive mice were similarly challenged with bacteria. Bacteria-challenged eyes were compared to uninoculated naive controls as was lens wear alone. Total RNA-sequencing determined corneal epithelium and bacterial gene expression. ResultsPrior lens wear profoundly altered the corneal response to P. aeruginosa, including: upregulated pattern-recognition receptors (tlr3, nod1), downregulated lectin pathway of complement activation (masp1), amplified upregulation of tcf7, gpr55, ifi205, wfdc2 (immune defense) and further suppression of efemp1 (corneal stromal integrity). Without lens wear, P. aeruginosa upregulated mitochondrial and ubiquinone metabolism genes. Lens wear alone upregulated axl, grn, tcf7, gpr55 (immune defense) and downregulated Ca2+-dependent genes necab1, snx31 and npr3. P. aeruginosa exposure to prior lens wearing vs. naive corneas upregulated bacterial genes of virulence (popD), its regulation (rsmY, PA1226) and antimicrobial resistance (arnB, oprR). ConclusionPrior lens wear impacts corneal epithelium gene expression altering its responses to P. aeruginosa and how P. aeruginosa responds to it favoring virulence, survival and adaptation. Impacted genes and associated networks provide avenues for research to better understand infection pathogenesis.

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Kumar, N. G., Grosser, M. R., Wan, S. J., Schator, D., Ahn, E., Jedel, E., Nieto, V., Evans, D. J., Fleiszig, S. M. J.. 2024-12-04. Contact Lens Wear Alters Transcriptional Responses to Pseudomonas aeruginosa in Both the Corneal Epithelium and the Bacteria. https://doi.org/10.1101/2024.12.03.626720

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