Association of High-Mobility Group Box-1 With Th Cell-Related Cytokines in the Vitreous of Ocular Sarcoidosis Patients.

Purpose: High-mobility group box-1 (HMGB1) is a nonhistone DNA-binding nuclear protein released from necrotic cells, which is also secreted by activated leukocytes and acts as a primary proinflammatory cytokine. In this study, we compared vitreous HMGB1 levels in ocular sarcoidosis with those in noninflammatory vitreoretinal diseases and evaluated its association with Th cell-related and proinflammatory cytokines.

Methods: The study group consisted of 24 patients with ocular sarcoidosis. The control group consisted of 27 patients with proliferative diabetic retinopathy (PDR) and 24 with idiopathic epiretinal membrane (ERM). Vitreous fluid samples were obtained at the beginning of vitrectomy. Vitreous levels of HMGB1 and IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, soluble CD40 ligand (sCD40L), and TNFα were measured.

Results: High-mobility group box-1 was detected in the vitreous of 23 of 24 patients (95.8%) with ocular sarcoidosis. Mean vitreous level of HMGB1 was the highest in the sarcoidosis group, followed by the PDR and ERM groups, with significant differences between the three groups. In the sarcoidosis group, vitreous levels of IL-6, IL-10, IL-31, IFN-γ, sCD40L, and TNFα were significantly higher than those in the idiopathic ERM group, and IFN-γ and sCD40L were significantly higher than those in the PDR group. Vitreous HMGB-1 level correlated significantly with IL-10, IFN-γ, and sCD40L levels but not with IL-6, IL-17, IL-31, or TNFα levels.

Conclusions: The vitreous level of HMGB1 is elevated in ocular sarcoidosis and is associated with vitreous levels of Th1- and regulatory T-related cytokines, but not with proinflammatory or Th17-related cytokines.