Overexpression of IL-17RC associated with ocular sarcoidosis

BACKGROUND: Sarcoidosis is a chronic inflammatory disease with a systemic granulomatous disorder affecting multiple organs including the eye. Both CD4(+) T cell and macrophage have been linked to the pathogenesis of the disease. METHODS: The expression of IL-17RC was measured using FACS,immunohistochemistry and real-time PCR. Serum level of IL-17 was detected using ELISA. RESULTS: An elevated expression of IL-17RC on CD8(+) T cells in peripheral blood was found in patients with ocular sarcoidosis as compared to healthy controls. Interestingly, we found a significant increase in the serum level of IL-17 in patients with ocular sarcoidosis as compared to healthy controls, which may be responsible for the induction of IL-17RC on CD8(+) cells. In addition, IL-17RC appeared only in the retinal tissue of the patient with clinically active sarcoidosis. CONCLUSIONS: Our results suggested a potential involvement of IL-17RC(+)CD8(+) T cells in pathogenesis of ocular sarcoidosis.