Purpose: To evaluate cytokine levels in the aqueous humor (AqH) of eyes with bullous keratopathy (BK) and low endothelial cell density (ECD).
Methods: A total of 145 AqH samples (60 BK, 16 low ECD, 35 corneal diseases with normal ECD, and 34 normal controls) were collected from consecutive patients who underwent corneal transplantation or cataract surgery. None of the patients had any clinically apparent inflammation at the time of AqH collection. The AqH levels of cytokines (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17A, IFN-α, IFN-γ, monocyte chemotactic protein [MCP]-1, TNF-α, E-selectin, P-selectin, soluble intercellular adhesion molecule [sICAM]-1, granulocyte-macrophage colony-stimulating factor [GM-CSF], macrophage inflammatory protein [MIP] -1α and MIP-1β) were compared among the groups.
Results: The levels of IL-1α, IL-8, IL-17A, TNF-α, GM-CSF, MIP-1α, IFN-γ, and E-selectin in the AqH were significantly elevated in BK and low ECD eyes, compared with healthy controls (all P < 0.03). The levels of IL-4, IL-6, IL-10, IL-12p70, IL-13, MCP-1, MIP-1β, P-selectin, and sICAM-1 were significantly elevated only in BK eyes, compared with healthy control (all P < 0.001). There were no significant differences in AqH cytokine levels between corneal diseases with normal ECD and normal control eyes. Among BK eyes, the IL-6 and IFN-γ levels were elevated in eyes with pseudophakic BK (PBK), Fuchs' endothelial corneal dystrophy (FECD), postkeratoplasty, posttrabeculectomy, and postlaser iridotomy (LI) (all, P < 0.04), whereas IL-1α, IL-10, IL-17A, MIP-1β, and sICAM-1 levels were elevated only in PBK, postkeratoplasty, posttrabeculectomy, and post-LI eyes (all, P < 0.05).
Conclusions: Subclinical elevation of AqH cytokine levels may cause endothelial cell loss.