Kinetics of Tear Fluid Proteins after Endothelial Keratoplasty and Predictive Factors for Recovery from Corneal Haze

Abstract

Endothelial keratoplasty (EK) is less invasive with faster recovery as compared to conventional penetrating keratoplasty, however, it relies on the clarity of the host corneal stroma. Corneal transplantation involves the induction of immune tolerance for allogeneic tissues as well as the corneal wound healing process, in which coordinated interactions between cytokines and growth factors are critical. In this study, we profiled the expression of 51 soluble factors in the tear fluid over the course of EK and have provided evidence of dynamic changes in cytokine expression in the ipsilateral and contralateral eyes. Cluster analyses classified the cytokine expression kinetics into five groups. Group 1 proteins included TGF-b1, IL-1b, and innate proinflammatory cytokines, which bilaterally increased after surgery, despite the use of topical corticosteroid in the transplanted eyes. Local corticosteroids suppressed cytokines involved in adaptive immunity in the transplanted eyes but not in the contralateral eyes. We found tear protein expression at baseline and one week post-surgery to be a potential predictive biomarker of delayed recovery after EK in terms of the corneal haze and visual acuity. Furthermore, Group 1 tear proteins were most associated with persistent corneal haze pre-surgery as well as visual acuity at one month-post transplant.

Regenerative Approaches and Future Trends for the Treatment of Corneal Burn Injuries

“…IL-1β is a main pro-inflammatory molecule also produced by activated monocytes, macrophages, and dendritic cells. Some of these soluble factors were also found to be expressed in tears upon analysis of bilateral tear fluid protein levels during the wound healing process after corneal endothelial keratoplasty [ 16 ]. Insights into other cytokines and chemokines involved in the corneal repair from injury came from a previous large-scale microarray analysis on cultured mouse corneal stromal cells [ 17 ].…”