Abstract
Purpose :
The exact mechanism of endothelial cell loss (ECL) after corneal transplantation is still poorly understood. We hypothesize that pre-existing microenvironmental alterations in aqueous humor (AqH) cause ECL after corneal transplantation. The purpose of this study is to evaluate the association between preoperative cytokine levels in AqH and ECL after penetrating keratoplasty (PKP).
Methods :
This prospective study included 68 human eyes. The AqH was collected at the beginning of PKP (37 eyes) and cataract surgery (31 control eyes). The cytokine levels (IL-1α, -1β, -2, -4, -6, -8, -10, -12p70, -13, -17A, IFN-α, IFN-γ, MCP-1, TNF-α, E-selectin, P-selectin, sICAM-1, GM-CSF, MIP-1α and MIP-1β) were measured using Luminex. The association of preoperative cytokine levels in AqH and postoperative ECL was evaluated.
Results :
The mean endothelial cell density (ECD±SD) was 2748±348 cells/mm2 (donor graft), 2021±766 at 1month, 1992±627 at 3 months and 1698±733 at 6 months after PKP. The preoperative AqH levels of IL-1α, -4, -6, -10, -12p70, -13, -17A, TNF-α, E-, P-selectin, and sICAM-1 were significantly higher in the PKP group than control (all, P<0.05). There were no significant correlations between cytokine levels and ECD at 3 months, however, ECD at 6 months was negatively correlated with the levels of IL-12p70 (r=-0.464, P=0.0088), IFNγ (r=-0.393, P=0.0194), MCP-1 (r=-0.369, P=0.029) and E-selectin (r=-0.377, P=0.031). The IL-12p70, IFNγ and E-selectin levels in eyes with ECD less than 1200 cells/mm2 at 6 months (15.7±12.9 pg/ml, 95.2±73.9 and 5167±4797) were significantly higher than eyes with ECD more than 1200 cells/mm2 at 6 months after PKP (7.4±3.2, 55.5±21.9 and 2537±1039, all P<0.05).
Conclusions :
Some of the patients with progressive ECL after PKP had higher levels of specific cytokines in AqH. Preoperative elevated aqueous cytokine levels, especially IL-12p70 and IFNγ, may cause progressive ECL after PKP.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.