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PubMed · 9808197

Enhanced HIV expression during Th2-oriented responses explained by the opposite regulatory effect of IL-4 and IFN-gamma of fusin/CXCR4.

G Galli·F Annunziato·C Mavilia·P Romagnani·L Cosmi·R Manetti·C Pupilli·E Maggi·S Romagnani
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Abstract

The human alpha-chemokine receptor fusin/CXCR4 is an important cofactor for entry of T lymphocyte-tropic HIV-1 strains. We investigated the possible regulatory role of T cell cytokine patterns on CXCR4 as well as HIV expression by using in vitro models of both secondary and primary immune responses. Antigen-specific memory CD4+ T cells infected with a T-tropic HIV-1 strain showed significantly higher CXCR4 and HIV-1 expression in Th0/2-oriented responses in comparison with Th1-oriented responses. Similarly, in naive CD4+ T cells activated in the presence of IL-4 or IL-12 and infected with the same T-tropic strain, IL-4 up-regulated whereas IL-12 down-regulated both CXCR4 and HIV-1 expression. The down-regulatory effect of IL-12 on CXCR4 expression was found to be dependent on its capacity to induce IFN-gamma production. These observations can account for the higher risk of progression in HIV-1-infected individuals undergoing Th0/2-oriented immune responses.

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Cells, CulturedDown-RegulationHIV Core Protein p24HIV-1HumansImmunologic MemoryInterferon-gammaInterleukin-4Receptors, CXCR4Th1 CellsTh2 CellsUp-RegulationJournal ArticleResearch Support, Non-U.S. Gov't

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G Galli, F Annunziato, C Mavilia, P Romagnani, L Cosmi, R Manetti, C Pupilli, E Maggi, S Romagnani. 1998. Enhanced HIV expression during Th2-oriented responses explained by the opposite regulatory effect of IL-4 and IFN-gamma of fusin/CXCR4.. https://doi.org/10.1002/(sici)1521-4141(199810)28%3A10%3C3280%3A%3Aaid-immu3280%3E3.0.co%3B2-m

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