Avidity of influenza-specific memory CD8+ T-cell populations decays over time compromising antiviral immunity.
Eur J Immunol
; 42(12): 3235-42, 2012 Dec.
Article
en En
| MEDLINE
| ID: mdl-22965681
ABSTRACT
Decline of cell-mediated immunity is often attributed to decaying T-cell numbers and their distribution in peripheral organs. This study examined the hypothesis that qualitative as well as quantitative changes contribute to the declining efficacy of CD8(+) T-cell memory. Using a model of influenza virus infection, where loss of protective CD8(+) T-cell immunity was observed 6 months postinfection, we found no decline in antigen-specific T-cell numbers or migration to the site of secondary infection. There was, however, a large reduction in antigen-specific CD8(+) T-cell degranulation, cytokine secretion, and polyfunctionality. A profound loss of high-avidity T cells over time indicated that failure to confer protective immunity resulted from the inferior functional capacity of remaining low avidity cells. These data imply that high-avidity central memory T cells wane with declining antigen levels, leaving lower avidity T cells with reduced functional capabilities.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Degranulación de la Célula
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Movimiento Celular
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Infecciones por Orthomyxoviridae
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Alphainfluenzavirus
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Inmunidad Celular
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Memoria Inmunológica
Tipo de estudio:
Prognostic_studies
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Qualitative_research
Límite:
Animals
Idioma:
En
Año:
2012
Tipo del documento:
Article