Purpose: To evaluate effects of rexinoid NEt-3IB on desiccating stress (DS) induced ocular surface disease, and monocyte/macrophage (MP/Mo) gene expression and latent time.

Methods: DS-induced dry eye was topically treated with rexinoid NEt-3IB (5 mM) or vehicle (Veh) 3x/day for 5 days. Gene profiling was performed by single-cell RNA-seq on conjunctival immune cells and by bulk RNA-seq on LPS-stimulated, dexamethasone (Dex,1 mM) or NEt-3IB (1-1000 nM) treated cultured Mo. Differentially expressed genes (DEG) and latent time were measured with scVelo. Permeability to Oregon Green Dextran (OGD) assessed corneal barrier, and conjunctival goblet cell (GC) parameters were measured in PAS-stained wholemounts.

Results: NEt-3IB significantly stimulates homeostatic, phagocytotic and anti-inflammatory gene expression, and suppresses inflammatory gene signatures in conjunctival Mo/MP lineage cells compared to Veh (adjP < 0.05). Latent time trajectory analysis further reveals that NEt-3IB preserves resident macrophage (rMP) gene expression profiles. Compared to Veh, cornea OGD uptake is lower (p=0.001), and conjunctival GC total (P=0.001) and single cell (P=0.01) areas are higher in the NEt-3IB group. The impact of NEt-3IB on DEGs in cultured Mo mirrors its effects in vivo. NEt-3IB and Dex suppress inflammatory mediator expression; however, NEt-3IB enhances the expression of homeostatic factors, including Igf1 and Il10, distinguishing a unique profile from a corticosteroid.

Conclusions: Rexinoid NEt-3IB suppresses inflammatory and stimulates homeostatic gene expression in the Mo/MP lineage and prevents DS-induced ocular surface disease. Rexinoid therapy is a novel approach to treat dry eye by stimulating endogenous production of homeostatic/anti-inflammatory factors.