HLA antigens in the iris and aqueous humor gamma interferon levels in anterior uveitis.

The induced expression of HLA antigens on a variety of tissues involved in autoimmune diseases has been reported by several groups. In this study, we have examined the expression of HLA antigens in iris biopsy specimens from patients with anterior uveitis and compared them to patients with noninflammatory senile cataracts. In addition, we measured the levels of gamma interferon in the aqueous humor of the same subjects. Our results show that there was induced expression of class I and class II HLA antigens in iris biopsies from patients with anterior uveitis and that the level of induced expression correlated with the concentration of gamma interferon found in the aqueous humor. These results suggest that induced expression of HLA antigens on iris cells may play a role in the pathogenesis of anterior uveitis and that gamma interferon may be one of the mediators for this induced expression.