Peptide motif for the rat MHC class II molecule RT1.Da: similarities to the multiple sclerosis-associated HLA-DRB1*1501 molecule.
Experimental autoimmune encephalomyelitis induced with myelin proteins in DA and LEW.1AV1 rats is a model of multiple sclerosis (MS). It reproduces major aspects of this detrimental disease of the central nervous system. MS is associated with the HLA-DRB1*1501, DRB5*0101, and DQB1*0602 haplotype. DA and LEW.1AV1 rats share the RT1av1 haplotype. So far, no MHC class II peptide motif of RT1.Da molecules has been described. Sequence alignment of the beta chain of the rat MHC class II molecule RT1.Da with human HLA class II molecules revealed strong similarity in the peptide-binding groove of RT1.Da and HLA-DRB1*1501. According to the putative peptide-binding pockets of RT1.Da, after comparison with the pockets of HLA-DRB1*1501, we predicted the peptide motif of RT1.Da. To verify the predicted motif, naturally processed peptides were eluted by acidic treatment from immunoaffinity-purified RT1.Da molecules of lymphoid tissue of DA rats and subsequently analyzed by ESI tandem mass spectrometry. In addition, we performed binding studies with combinatorial nonapeptide libraries to purified RT1.Da molecules. Based on these studies we could define a peptide-binding motif for RT1.Da characterized by aliphatic amino acid residues (L, I, V, M) and of F for the peptide pocket P1, aromatic residues (F, Y, W) for P4, basic residues (K, R) for P6, aliphatic residues (I, L, V) for P7, and aromatic residues (F, Y, W) and L for P9. Both methods revealed similar binding characteristics for peptides to RT1.Da. This data will allow epitope predictions for analysis of peptides, relevant for experimental autoimmune diseases.
Duyar
Hüseyin
H
Experimental Neuroimmunology Laboratory, Department of General Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, Hoppe-Seyler-Strasse 3, 72076, Tübingen, Germany.
Dengjel
Jörn
J
de Graaf
Katrien L
KL
Wiesmüller
Karl-Heinz
KH
Stevanović
Stefan
S
Weissert
Robert
R
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D019295:Computational Biology; D005260:Female; D006684:HLA-DR Antigens / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D059811:HLA-DRB1 Chains; D006649:Histocompatibility Antigens / Q000737:chemistry* / Q000378:metabolism; D000949:Histocompatibility Antigens Class II / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009103:Multiple Sclerosis / Q000235:genetics / Q000276:immunology*; D019151:Peptide Library; D010455:Peptides / Q000276:immunology / Q000378:metabolism; D051381:Rats; D016415:Sequence Alignment
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D006649:Histocompatibility Antigens; D000949:Histocompatibility Antigens Class II; D019151:Peptide Library; D010455:Peptides; C038353:histocompatibility antigens RT, rat