Uveitis induced in primates by IRBP: humoral and cellular immune responses

In a previous publication, we have reported that immunization with bovine interphotoreceptor retinoid-binding protein (IRBP) produces severe uveitis in monkeys. The present study further examined the uveitogenicity of IRBP and analysed the immune responses in the immunized monkeys. Uveitis developed in monkeys immunized with bovine IRBP at doses as low as 10 micrograms Kg-1 body wt. In contrast, no disease was detected in monkeys immunized with monkey IRBP at the total dose of 100 micrograms Kg-1. Serum antibodies were measured in the immunized monkeys by the enzyme-linked immunosorbent assay, while cellular immunity was determined by skin hypersensitivity and the lymphocyte mitotic reaction in culture. No humoral or cellular immune responses were detected in monkeys immunized with monkey IRBP. Monkeys immunized with bovine IRBP produced antibodies which cross-reacted well with monkey IRBP. On the other hand, these monkeys did not react with monkey IRBP by skin hypersensitivity and their lymphocytes responded in culture to this protein only when tested by a highly sensitive procedure. In contrast, significant responses of the same cells to bovine IRBP were obtained at all tested conditions. These data are interpreted to suggest that the pathogenic cellular immune responses in vivo detect cross-reactivity with this autologous ocular antigen more efficiently than most conventional laboratory tests.