Immunological self, nonself discrimination.
Science
; 235(4791): 865-70, 1987 Feb 20.
Article
em En
| MEDLINE
| ID: mdl-2433769
ABSTRACT
The ability of immunodominant peptides derived from several antigen systems to compete with each other for T cell activation was studied. Only peptides restricted by a given transplantation antigen are mutually competitive. There is a correlation between haplotype restriction, ability to bind to the appropriate transplantation antigen, and ability to inhibit activation of other T cells restricted by the same transplantation antigen. An exception was noted in that a peptide derived from an antigen, bacteriophage lambda cI repressor, binds to the I-Ed molecule in a specific way, yet is not I-Ed-restricted. Comparison of the sequence of the repressor peptide with that of other peptides able to bind to (and be restricted by) I-Ed and a polymorphic region of the I-Ed molecule itself revealed a significant degree of homology. Thus, peptides restricted by a given class II molecule appear to be homologous to a portion of the class II molecule itself. The repressor-derived peptide is identical at several polymorphic residues at this site, and this may account for the failure of I-Ed to act as a restriction element. Comparison of antigenic peptide sequences with transplantation antigen sequences suggests a model that provides a basis for explaining self, nonself discrimination as well as alloreactivity.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Receptores Imunológicos
/
Linfócitos T
/
Antígenos de Histocompatibilidade Classe II
/
Proteínas de Ligação a DNA
/
Antígenos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Science
Ano de publicação:
1987
Tipo de documento:
Article