Elevated levels of interleukin 6 in the vitreous fluid of patients with pars planitis and posterior uveitis: the Massachusetts eye & ear experience and review of previous studies

Abstract

Introduction: Although the exact mechanisms that lead to uveitis are not entirely known, the role of cytokines in the pathogenesis of this disease has been shown to be important. Prior studies described the presence of an array of cytokines in the intraocular fluid of patients with uveitis. Review of these studies indicate that Interleukin-6 (IL-6) is present, and animal data suggest the important role of IL-6 in the regulation of ophthalmologic immune responses.

Purpose: We investigated whether IL-6, TNF-alpha, IL-1 alpha, beta, IL-2 are present in the vitreous of patients with active intermediate and posterior uveitis.

Methods: Vitreous specimens were collected from 23 eyes of patients with active intermediate and posterior uveitis who underwent diagnostic or therapeutic vitrectomies. TNF-alpha, IL-1 alpha and beta, IL-2 and IL-6 were measured by enzyme-linked immunosorbent assay. Eight vitreous fluid samples from eye bank eyes were used as control.

Results: IL-6 was higher in the vitreous of patients with uveitis compared to control samples (p = 0.0119). No TNF-alpha, IL-2, IL1-alpha or beta was detected. The levels of IL-6 did not correlate with a specific clinical diagnosis, but patients with pars planitis and panuveitis had the highest levels (p = 0.58)

Conclusions: IL-6 is elevated in the vitreous of patients with active intermediate and posterior uveitis.