Leptin increases in Vogt-Koyanagi-Harada (VKH) disease and promotes cell proliferation and inflammatory cytokine secretion.

BACKGROUND/AIMS: [corrected] Leptin has recently been found to play an important role in the development of autoimmune diseases. Our study is designed to investigate the expression and possible role of leptin in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease, one of the common types of autoimmune uveitis in China.

METHODS

Leptin levels in serums of 20 active, 16 inactive VKH patients and 20 healthy controls were measured using ELISA. Peripheral blood mononuclear cells (PBMCs) separated from active VKH patients and healthy controls were cultured with recombinant human leptin, and cell proliferation was assayed by [(3)H]-TdR incorporation. Cytokine levels in the supernatant of PBMCs cultured in mixed lymphocyte reaction (MLR) upon stimulation with leptin were assayed by ELISA.

RESULTS

Our results showed that leptin was significantly increased in the serum of active VKH patients compared with that in inactive VKH patients and healthy controls. Leptin levels in active VKH patients remained markedly higher when divided by body mass index (BMI). PBMCs cultured with leptin induced a marked cell proliferation and profound secretion of IFN-gamma and IL-17.

CONCLUSION

These findings suggest that leptin may be involved in the development of VKH disease possibly by promoting an immune response.