[Unique immunological properties of short forms of the interphotoreceptor retinoid-binding protein derived uveitogenic peptide].
Interphotoreceptor retinoid-binding protein (IRBP) induces experimental autoimmune uveoretinitis in a variety of animals. We have previously shown that sequence 1169-1191 of bovine IRBP has strong uveitogenicity and immunogenicity in Lewis rats. In this study, two completely distinct antigenic sites were detected within a short form of this peptide. One site is localized in sequence 1182-1191. The second site localizes within sequence 1183-1191 and becomes detectable only when tryptophan at 1182 is deleted. Lymphocytes sensitized against the first determinant recognized a longer peptide as well as whole IRBP. Lymphocytes sensitized against the second determinant recognized only two peptides 1184-1191 and 1183-1191. No cross reactivity was detected between these two determinants. Amino acid substitution of tryptophan with alanine or glutamic acid at 1182 in peptide 1182-1191 caused complete loss of uveitogenicity and immunogenicity, while substitution with phenylalanine did not change any immunological activities of the original peptide. The unique immunological properties of IRBP-derived peptides were discussed.
Kotake
S
S
Department of Ophthalmology, Hokkaido University School of Medicine, Sapporo, Japan.
Sanui
H
H
Gery
I
I
D000595:Amino Acid Sequence; D000818:Animals; D001324:Autoantigens / Q000276:immunology; D001327:Autoimmune Diseases / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D005136:Eye Proteins; D008297:Male; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology*; D051381:Rats; D011919:Rats, Inbred Strains; D012173:Retinitis / Q000276:immunology; D012177:Retinol-Binding Proteins / Q000276:immunology*; D014605:Uveitis / Q000276:immunology*; D000099214:Retinol-Binding Proteins, Interstitial
D001324:Autoantigens; D000939:Epitopes; D005136:Eye Proteins; D010446:Peptide Fragments; D012177:Retinol-Binding Proteins; D000099214:Retinol-Binding Proteins, Interstitial