Study of antigen-processing steps reveals preferences explaining differential biological outcomes of two HLA-A2-restricted immunodominant epitopes from human immunodeficiency virus type 1.
J Virol
; 76(20): 10219-25, 2002 Oct.
Article
em En
| MEDLINE
| ID: mdl-12239297
ABSTRACT
Cytotoxic T-lymphocyte (CTL) responses directed to different human immunodeficiency virus (HIV) epitopes vary in their protective efficacy. In particular, HIV-infected cells are much more sensitive to lysis by anti-Gag/p17(77-85)/HLA-A2 than to that by anti-polymerase/RT(476-484)/HLA-A2 CTL, because of a higher density of p17(77-85) complexes. This report describes multiple processing steps favoring the generation of p17(77-85) complexes (i) the exact COOH-terminal cleavage of epitopes by cellular proteases occurred faster and more frequently for p17(77-85) than for RT(476-484), and (ii) the binding efficiency of the transporter associated with antigen processing was greater for p17(77-85) precursors than for the RT(476-484) epitope. Surprisingly, these peptides, which differed markedly in their antigenicity, displayed qualitatively and quantitatively similar immunogenicity, suggesting differences in the mechanisms governing these phenomena. Here, we discuss the mechanisms responsible for such differences.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Virais
/
Cisteína Endopeptidases
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Linfócitos T Citotóxicos
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Antígenos HIV
/
Produtos do Gene gag
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Infecções por HIV
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Antígeno HLA-A2
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Epitopos Imunodominantes
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HIV-1
/
Apresentação de Antígeno
Limite:
Humans
Idioma:
En
Revista:
J Virol
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
França