Dendritic cells and HIV specific CD4(+) T cells: HIV antigen presentation, T-cell activation, and viral transfer

Groupe Virus et Immunité, Unité de Recherche Associée (URA) Centre National de la Recherche Scientifique (CNRS) 1930, Paris, France.
Blood (Impact Factor: 10.43). 10/2006; 108(5):1643-51. DOI: 10.1182/blood-2006-02-006361
Source: PubMed

ABSTRACT Human immunodeficiency virus (HIV)-specific CD4+ lymphocytes are preferentially infected in HIV-positive individuals. To study this preferential infection, we have derived several HIV-specific (HS) CD4+ clones. We show that in dendritic cells (DCs), HIV virion capture led to major histocompatibility complex class-II (MHC-II)-restricted viral antigen presentation and to activation of HS cells. In contrast, neither cell-free virions nor infected lymphocytes activated HS cells. In DCs, the dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN/CD209), which internalizes virions, promoted MHC-II presentation of HIV antigens. Activation of HS cells by HIV-exposed DCs triggered an efficient viral spread in lymphocytes. CD4+ clones with irrelevant antigenic specificities were not activated by HIV-exposed DCs and poorly supported viral replication under this setting. Our results unravel the mechanisms of MHC-II-restricted HIV antigen presentation by DCs and describe how HIV gains access to the very cells designed by the immune system to counteract this pathogen.

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    • "HI FBS as previously described [34]. Adult and newborn MoDCs were then washed and 7 Â "
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    Biomaterials 07/2014; 35(31). DOI:10.1016/j.biomaterials.2014.06.043 · 8.31 Impact Factor
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    • "Mature DCs capture HIV-1 through an envelope-independent mechanism (Izquierdo-Useros et al., 2007), retaining viral particles in a non-conventional compartment enriched in CD63 and CD81 tetraspanins (Garcia et al., 2005; Izquierdo-Useros et al., 2007). In immature DCs, the HIV envelope and DC-SIGN-dispensable pathways account for about 50% of antigen presentation through MHC-II molecules (Moris et al., 2006). DCs are also able to capture envelope-pseudotyped virus-like particles through a DC-SIGN-independent pathway, activating autologous naïve CD4 + T cells (Buonaguro et al., 2006). "
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    Cellular Microbiology 10/2010; 13(1):10-7. DOI:10.1111/j.1462-5822.2010.01542.x · 4.82 Impact Factor
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    • "Stimulator cells were then cocultured for at least 24–36 hr with CD4 + T cell clones. IFN-γ production was measured in an enzyme-linked immunosorbent spot (ELISPOT) assay as described (Buseyne et al., 2001; Moris et al., 2006) with a MABTECH IFN-γ ELISPOT assay kit (MABTECH, Sweden). As a positive control, stimulators were incubated with cognate peptides (0.5 mg/ml) before addition of CD4 + clones. "
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