INTERFERON-GAMMA (IFN-GAMMA) PRODUCTION INVIVO IN EXPERIMENTAL AUTOIMMUNE UVEORETINITIS

Experimental autoimmune uveoretinitis (EAU) is a well-characterized model of immune-mediated intraocular inflammation. The intraocular infiltrate in EAU consists predominantly of T lymphocytes. The in vivo production of interferon-gamma (IFN-gamma) by these T cells was investigated immunohistochemically and by in situ hybridization using a cDNA probe to rat IFN-gamma mRNA. Positive localization of IFN-gamma mRNA began simultaneously with disease onset and increased as the inflammatory tissue destruction progressed. The positive signal was seen on cells in the retina, uveal tract and extraocular region where collections of inflammatory cells contained many T lymphocytes. Numerous cells in these locations also stained positively immunohistochemically for IFN-gamma. These results indicate that the in vivo production of IFN-gamma within the eye could play a role in the immune regulation of intraocular inflammatory disease.