We examined the direct binding of a hen egg white lysozyme peptide, HEL(46-61), to membrane I-A(k) (protein encoded in the A locus of the I region) molecules in the presence of detergent. A number of synthetic peptide derivatives, which did not stimulate our T-cell reactive hybridomas, competed for the binding of HEL(46-61) to I-Aκ and also inhibited the functional presentation of HEL (46-61). Inhibitors included a peptide lacking a tyrosine at position 53 and a peptide corresponding to the autologous lysozyme peptide. Presentation was examined with cells or with supported planar phospholipid membranes bearing only I-A(k) and HEL(46-61). Other peptides that did not complete for the binding did not inhibit functional presentation. We concluded that the binding of an immunogenic peptide to I-A is critical for presentation, that the I-A molecule does not discriminate between autologous and foreign related determinants but does recognize structurally different peptides. Our evidence suggests that our immunogenic peptide bears noncontiguous amino acids critical for contact I-A binding interspersed with amino acids critical for interaction with T cells.
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - 1986|