Single amino acid residues in a synthetic peptide of influenza haemagglutinin, HA 1 177-199, distinguish I-Ad- and I-Ed-restricted T-cell epitopes.
A majority of Iad-restricted, CD4+ T-cell clones, derived from BALB/c mice infected with X31 (H3N2) influenza virus and specific for the HA 1 subunit of the viral haemagglutinin (HA), has previously been shown to recognize the synthetic peptide HA 1 177-199, corresponding to the primary amino acid sequence of a major antibody binding site. Here it is demonstrated that both I-Ad- and I-Ed-restricted T-cell clones recognize HA 1 177-199, and that inter- and intra-allelic differences in Iad-restricted recognition are defined by single amino acid residues. A panel of truncated HA 1 synthetic peptides defined three distinct but overlapping CD4+ epitopes within the common antigenic site (HA 1 177-199): two I-Ad-restricted epitopes mapped within HA 1 186-198 and HA 1 177-199, and peptide HA 1 178-195 identified an I-Ed-restricted epitope. Moreover, fine specificity differences in the recognition of synthetic peptides, truncated at the carboxy terminus of HA 1 177-199, identified residues HA 1 A 198 and HA 1 S 199 as being critical for defining inter- and intra-allelic differences, respectively, in the Iad-restricted T-cell recognition of HA.
National Institute for Medical Research, Mill Hill, London.
B C
BC
Barnett
I
I
Hartlmayr
C M
CM
Graham
D B
DB
Thomas
D000596:Amino Acids / Q000276:immunology; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D000939:Epitopes / Q000032:analysis*; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D010455:Peptides / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000276:immunology
D000596:Amino Acids; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral; D000949:Histocompatibility Antigens Class II; D010455:Peptides; D014759:Viral Envelope Proteins