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Viral MHC class I inhibition evades CD8+ T-cell effector responses in vivo but not CD8+ T-cell priming.

ABSTRACT: Although viral MHC class I inhibition is considered a classic immune-evasion strategy, its in vivo role is largely unclear. Mutant cowpox virus lacking its MHC class I inhibitors is markedly attenuated during acute infection because of CD8(+) T-cell-dependent control, but it was not known how CD8(+) T-cell responses are affected. Interestingly, we found no major effect of MHC class I down-regulation on priming of functional cowpox virus-specific CD8(+) T cells. Instead, we demonstrate that, during acute infection in vivo, MHC class I down-regulation prevents primed virus-specific CD8(+) T cells from recognizing infected cells and exerting effector responses to control the infection.

SUBMITTER: Gainey MD

PROVIDER: S-EPMC3511129 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Viral MHC class I inhibition evades CD8+ T-cell effector responses in vivo but not CD8+ T-cell priming.

Gainey Maria D MD Rivenbark Joshua G JG Cho Hyelim H Yang Liping L Yokoyama Wayne M WM

Proceedings of the National Academy of Sciences of the United States of America 20121029 47

Although viral MHC class I inhibition is considered a classic immune-evasion strategy, its in vivo role is largely unclear. Mutant cowpox virus lacking its MHC class I inhibitors is markedly attenuated during acute infection because of CD8(+) T-cell-dependent control, but it was not known how CD8(+) T-cell responses are affected. Interestingly, we found no major effect of MHC class I down-regulation on priming of functional cowpox virus-specific CD8(+) T cells. Instead, we demonstrate that, duri ...[more]

PMID: 23112205

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