Synthetic peptides anchor T cell-specific TNP epitopes to MHC antigens.
Several TNP-specific, H-2Kb-restricted mouse CTL clones were identified which specifically lysed target cells in the presence of tryptic digests of TNP-modified BSA. Glutaraldehyde fixation of cells revealed that the tryptic fragments did not require further cellular processing. Chromatographic fractionation of digested TNP-BSA identified the peptide TNP-BSA222-231, containing a TNP-modified lysine at BSA position 227, as the antigenic entity. The corresponding synthetic peptide was immunologically cross-reactive with the digest. All clones reactive with TNP-BSA222-231 cross-reacted with a similar peptide from mouse serum albumin (TNP-MSA126-135), favoring the assumption that TNP-BSA222-231 represents an artificial determinant, cross-reacting with some as yet unidentified, TNP-modified, Kb-associated self-peptides. Some of our clones also cross-reacted with tryptic digests of TNP-OVA or TNP-keyhole limpet hemocyanin. We interpret these findings to indicate that 1) a significant proportion of hapten (TNP) determinants for T cells are anchored to MHC via peptides; and 2) the amino acid sequence of these peptides may only partly define the specificity of the T cell-relevant hapten epitope, implying a particularly repetitive nature of these determinants. The production of T cell-antigenic hapten-peptide conjugates will hopefully open new roads to study immune responses to environmental allergens.
Max-Planck-Institut für Immunbiologie, Universität, Freiburg, FRG.
B
B
Ortmann
S
S
Martin
A
A
von Bonin
E
E
Schiltz
H
H
Hoschützky
H U
HU
Weltzien
D000595:Amino Acid Sequence; D000818:Animals; D000939:Epitopes; D006183:H-2 Antigens / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010047:Ovalbumin / Q000276:immunology; D010446:Peptide Fragments / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology*
D000939:Epitopes; D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D010446:Peptide Fragments; D014301:Trinitrobenzenes; D012710:Serum Albumin, Bovine; D010047:Ovalbumin