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Chronic exposure to type-I IFN under lymphopenic conditions alters CD4 T cell homeostasis.

ABSTRACT: HIV infection and the associated chronic immune activation alter T cell homeostasis leading to CD4 T cell depletion and CD8 T cell expansion. The mechanisms behind these outcomes are not totally defined and only partially explained by the direct cytopathic effect of the virus. In this manuscript, we addressed the impact of lymphopenia and chronic exposure to IFN-? on T cell homeostasis. In a lymphopenic murine model, this interaction led to decreased CD4 counts and CD8 T cell expansion in association with an increase in the Signal Transducer and Activator of Transcription 1 (STAT1) levels resulting in enhanced CD4 T cell responsiveness to IFN-?. Thus, in the setting of HIV infection, chronic stimulation of this pathway could be detrimental for CD4 T cell homeostasis.

SUBMITTER: Le Saout C

PROVIDER: S-EPMC3946368 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Chronic exposure to type-I IFN under lymphopenic conditions alters CD4 T cell homeostasis.

Le Saout Cecile C Hasley Rebecca B RB Imamichi Hiromi H Tcheung Lueng L Hu Zonghui Z Luckey Megan A MA Park Jung-Hyun JH Durum Scott K SK Smith Mindy M Rupert Adam W AW Sneller Michael C MC Lane H Clifford HC Catalfamo Marta M

PLoS pathogens 20140306 3

HIV infection and the associated chronic immune activation alter T cell homeostasis leading to CD4 T cell depletion and CD8 T cell expansion. The mechanisms behind these outcomes are not totally defined and only partially explained by the direct cytopathic effect of the virus. In this manuscript, we addressed the impact of lymphopenia and chronic exposure to IFN-α on T cell homeostasis. In a lymphopenic murine model, this interaction led to decreased CD4 counts and CD8 T cell expansion in associ ...[more]

PMID: 24603698

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Chronic exposure to type-I IFN under lymphopenic conditions alters CD4 T cell homeostasis.

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Chronic exposure to type-I IFN under lymphopenic conditions alters CD4 T cell homeostasis.

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