• Cornea/External Disease

    This experimental study found that topical treatment with interleukin-1 receptor antagonist (IL-1Ra) was effective at ameliorating clinical signs and reducing underlying inflammation in a mouse model of dry eye disease. The effects were comparable to those resulting from treatment with topical methylprednisolone.

    Dry eye disease was induced in C57BL/6 female mice through exposure to a desiccating environment within a controlled environment chamber. Topical formulations containing 5% IL-1Ra, 1% methylprednisolone, 0.05% cyclosporin A, and a vehicle control containing carboxymethylcellulose sodium were applied after the induction of dry eye. Corneal fluorescein staining was performed in the treatment groups by a masked observer.

    IL-1Ra–treated eyes had a significant reversal in corneal epithelial damage, indicated by decreased fluorescein staining, as compared with the untreated and vehicle-treated groups. There was a significant decrease in corneal fluorescein staining with 1% methylprednisolone (P < 0.01) and 0.05% cyclosporin A (P < 0.03).

    Treatment with 5% IL-1Ra and 1% methylprednisolone also produced a significant decrease in the number of central corneal CD11b+ cells (P < 0.05), corneal lymphatic growth (P < 0.05) and corneal interleukin-1β expression (P < 0.003) compared with vehicle.

    The authors noted that dry eye corneas treated with IL-1Ra showed a significant decrease in lymphatic growth. Downregulation of IL-1β could reduce the lymphangiogenesis in the mouse cornea through diminished production of potent prolymphangiogenic factors, vascular endothelial growth factor-C and vascular endothelial growth factor-D. Treatment with IL-1Ra also may act by suppressing T helper cell activity at the ocular surface.

    These data, the authors conclude, suggest that the use of topical IL-1Ra shows promise as a therapeutic method for dry eye disease and possibly in other inflammatory conditions of the cornea and ocular surface.