Tolerance to p53 by A2.1-restricted cytotoxic T lymphocytes.
J Exp Med
; 185(5): 833-41, 1997 Mar 03.
Article
em En
| MEDLINE
| ID: mdl-9120389
ABSTRACT
Elevated levels of the p53 protein occur in approximately 50% of human malignancies, which makes it an excellent target for a broad-spectrum T cell immunotherapy of cancer. A major barrier to the design of p53-specific immunotherapeutics and vaccines, however, is the possibility that T cells may be tolerant of antigens derived from wild-type p53 due to its low level of expression in normal thymus and lymphohemopoetic cells. The combination of p53 deficient (p53-/-) and p53+/+ HLA-A2.1/Kb transgenic mice was used as a model to explore the possibility that A2.1-restricted cytotoxic T lymphocytes (CTL) are functionally tolerant of self peptides derived from the wild-type p53 tumor suppressor protein. A2.1-restricted CTL specific for a naturally processed p53 self-epitope spanning residues 187-197 were completely aborted in p53+/+ as opposed to p53-/- transgenic mice. In contrast, CTL specific for a second self-epitope spanning residues 261-269 of the murine p53 sequence were detected in both p53-/- and p53+/+ A2.1/Kb transgenic mice. However, the avidity of the CTL effectors obtained from p53+/+ mice was 10-fold lower than that obtained from p53-/- mice, again suggesting elimination of CTL with high avidity for the A2.1-peptide complex. The circumvention of functional tolerance of high avidity CTL may therefore be a necessary prerequisite for optimizing immunotherapy against A2.1-restricted wild-type p53 epitopes in humans.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fragmentos de Peptídeos
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Linfócitos T Citotóxicos
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Antígenos H-2
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Proteína Supressora de Tumor p53
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Tolerância Imunológica
Limite:
Animals
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Humans
Idioma:
En
Revista:
J Exp Med
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Estados Unidos