Abstract
Purpose: :
Previously we reported that interleukin–8 (IL–8) was constitutively expressed in normal human basal and reflex tears with the concentrations of 731.4 +/–116.2 (mean +– SEM) pg/ml and 276 +/– 47.5 pg/ml, respectively. The aim of this study is to elucidate IL–8 levels in tear fluids during diseased ocular status and to clarify the time course of IL–8 levels in tear fluids post epithelial transplantation.
Methods: :
Tear samples were collected from a total of 220 eyes with various diseases affecting cornea and/or conjunctiva. IL–8 in tear fluids was measured by enzyme–linked immunosorbent assay (ELISA).
Results: :
Extremely high levels of IL–8 were detected in the eyes with Stevens–Johnson syndrome (SJS) at the acute stage, chemical injury, thermal injury, and graft versus host disease (22.1 +/– 12.4 ng/ml, 21.7 +/– 15.2 ng/ml, 24.5 +/– 11.2 ng/ml and 29.4 +/– 13.1 ng/ml, respectively). IL–8 in tear fluids was moderately elevated in the eyes with SJS at the chronic stage, peripheral corneal ulcer, bullous keratopathy, and allergic conjunctivitis. In contrast, IL–8 levels were low in the eyes with corneal dystrophy, post–penetrating keratoplasty, and post–corneal infection. IL–8 elevation continued several months after severe chemical or thermal injury, especially in the eyes with persistent epithelial defect. IL–8 levels post epithelial transplantation were significantly higher in SJS, ocular pemphigoid, and thermal injury compared to in aniridia and neoplasia.
Conclusions: :
IL–8 levels in tear fluids greatly reflected ocular surface inflammation. High levels of IL–8 indicated the necessity of anti–inflammatory therapy such as general and/or topical steroids. From the clinical view point, IL–8 in tear fluids can be a monitor of the degree of inflammation of ocular surface diseases.
Keywords: cytokines/chemokines • cornea: epithelium • inflammation