Chinese origin rhesus macaque major histocompatibility complex class I molecules promiscuously present epitopes from SIV associated with molecules of Indian origin; implications for immunodominance and viral escape.
Immunogenetics
; 63(9): 587-97, 2011 Sep.
Article
em En
| MEDLINE
| ID: mdl-21626440
ABSTRACT
The presentation of identical peptides by different major histocompatibility complex class I (MHC-I) molecules, termed promiscuity, is a controversial feature of T cell-mediated immunity to pathogens. The astounding diversity of MHC-I molecules in human populations, presumably to enable binding of equally diverse peptides, implies promiscuity would be a rare phenomenon. However, if it occurs, it would have important implications for immunity. We screened 77 animals for responses to peptides known to bind MHC-I molecules that were not expressed by these animals. Some cases of supposed promiscuity were determined to be the result of either non-identical optimal peptides or were simply not mapped to the correct MHC-I molecule in previous studies. Cases of promiscuity, however, were associated with alterations of immunodominance hierarchies, either in terms of the repertoire of peptides presented by the different MHC-I molecules or in the magnitude of the responses directed against the epitopes themselves. Specifically, we found that the Mamu-B*01701-restricted peptides Vif HW8 and cRW9 were also presented by Mamu-A2*0526 and targeted by an animal expressing that allele. We also found that the normally subdominant Mamu-A1*00101 presented peptide Gag QI9 was also presented by Mamu-B*05601. Both A2*0526 and B*05601 are molecules typically or exclusively expressed by animals of Chinese origin. These data clearly demonstrate that MHC-I epitope promiscuity, though rare, might have important implications for immunodominance and for the transmission of escape mutations, depending on the relative frequencies of the given alleles in a population.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Genes MHC Classe I
/
Epitopos Imunodominantes
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Síndrome de Imunodeficiência Adquirida dos Símios
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Vírus da Imunodeficiência Símia
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Macaca mulatta
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Revista:
Immunogenetics
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Estados Unidos