DO11.10 and OT-II T cells recognize a C-terminal ovalbumin 323-339 epitope.
The OVA323-339 epitope recognized by DO11.10 (H-2d) and OT-II (H-2b) T cells was investigated using amino- and carboxy-terminal truncations to locate the approximate ends of the epitopes and single amino acid substitutions of OVA323-339 to identify critical TCR contact residues of the OVA323-339 peptide. DO11.10 and OT-II T cells are both specific for a C-terminal epitope whose core encompasses amino acids 329-337. Amino acid 333 was identified as the primary TCR contact residue for both cells, and amino acid 331 was found to be an important secondary TCR contact residue; however, the importance of other secondary TCR contact residues and peptide flanking residues differ between the cells. Additional OVA323-339-specific clones were generated that recognized epitopes found in the N-terminal end or in the center of the peptide. These findings indicate that OVA323-339 can be presented by I-Ad in at least three binding registers. This study highlights some of the complexities of peptide Ags such as OVA323-339, which contain a nested set of overlapping T cell epitopes and MHC binding registers.
Robertson
J M
JM
Department of Microbiology and Immunology, Emory University, Atlanta, GA 30322, USA.
Jensen
P E
PE
Evavold
B D
BD
D000595:Amino Acid Sequence; D000818:Animals; D017951:Antigen Presentation; D002450:Cell Communication / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology / Q000378:metabolism*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D016056:Immunodominant Epitopes / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D010047:Ovalbumin / Q000276:immunology* / Q000378:metabolism*; D010446:Peptide Fragments / Q000276:immunology* / Q000378:metabolism*; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*
D018984:Epitopes, T-Lymphocyte; D000949:Histocompatibility Antigens Class II; D016056:Immunodominant Epitopes; C111390:OVA 323-339; D010446:Peptide Fragments; D010047:Ovalbumin