IL-12 inhibits endotoxin-induced inflammation in the eye

Abstract

Interleukin-12 (IL-12) is a heterodimeric cytokine that induces interferon (IFN)-gamma production and an increased generation of Th 1 cells. Both IL-12 and IL-12 antagonists are being studied for the treatment of allergic reactions, autoimmune disease and malignancy. the goal of the present experiments was to examine the importance of IL-12 in endotoxin-induced ocular inflammation. the number of inflammatory cells infiltrating eyes with endotoxin-induced uveitis (EIU) was significantly increased in animals treated with intraperitoneal anti-IL-12 antibody when compared to control animals, but there was no difference in infiltrating inflammatory cells in the eyes of animals treated with IL-12 when compared to controls. in contrast, intraocular injection of IL-12 significantly inhibited the development of endotoxin-induced intraocular inflammation. the inflammatory cells were reduced in the eves of animals receiving intraocular IL-obtained from eyes with EIU showed increased levels of IFN-gamma and decreased levels of IL-6 in eyes receiving intraocular IL-12. These data show that IL-12 has an inhibitory effect on endotoxin-induced inflammation in the eye and su that IL-12 can have an immunoregulatory function in some forms of inflammatory disease.