[Analysis of immune responses of uveitogenic synthetic peptides derived from IRBP].

We reported that R4 and R14 are uveitogenic synthetic peptides derived from bovine IRBP (interphotoreceptor retinoid-binding protein) in rats. R4 induced mild uveitis, while R14 induced severe uveitis with retinal detachment. In this experiment, a comparison of uveitogenicity, immune responses and capacity of uveitis transfer was made between R4 and R14. R14 was found to be approximately 1,000 times more uveitogenic than R4. R14 showed cross-reactivity with IRBP, original antigen, but R4 did not in lymphocytic proliferation assay and adoptive transfer experiment. Neither R4 nor R14 exhibited cross-reactivity with IRBP in antibody production in sera. Therefore, R14 is found to be an immunodominant site in the whole sequence of IRBP. It is conceivable that R14 plays an important role in uveitis induction and immune responses in rat immunized IRBP.