Purpose:
The purpose of the present study was to investigate the effect of cysteamine on experimental autoimmune uveitis (EAU) in mice and provide new insights for the treatment of human uveitis.
Methods:
EAU was induced in female C57BL/6 wild-type mice by a footpad injection of human IRBP1-20 (250ug/mouse) emulsified in complete Freud adjuvant (CFA). From one day before the IRBP inoculation, cysteamine, TG inhibitor was daily administered by intraperitoneal injection. Control group received the same amount of vehicle only. After 1 week, the draining lymph nodes were collected, and T lymphocytes were analyzed for cytokine assay by intracellular staining. In addition, clinical, histopathology, and TG activity were analyzed.
Results:
A single immunization of IRBP peptide led to cellular infiltrates and significant structural damage of the retina. Disease onset was significantly delayed in cysteamine-treated mice (14.6 days) compared to untreated mice (12.1 days, p=0.02). The number of inflammatory cells, the TG activity, and the levels of Th1 and Th17-type cytokines in the groups treated with cysteamine were decreased. Alteration was not found in Th2-type cytokines. The cytokine expression was correlated with the inflammatory activity.
Conclusions:
The results suggest that cysteamine has an anti-inflammatory effect that is due to the blocking of the expression of Th1 and Th17 cytokines. This finding demonstrated the therapeutic potential of cysteamine for the control of endogenous ocular inflammatory diseases.
Keywords: uveitis-clinical/animal model • cytokines/chemokines • inflammation