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. 2005 Aug;79(15):9618-24.
doi: 10.1128/JVI.79.15.9618-9624.2005.

The promiscuous CC chemokine receptor D6 is a functional coreceptor for primary isolates of human immunodeficiency virus type 1 (HIV-1) and HIV-2 on astrocytes

Stuart J D Neil  1 , Marlen M I Aasa-Chapman, Paul R Clapham, Robert J Nibbs, Aine McKnight, Robin A Weiss
Affiliations

The promiscuous CC chemokine receptor D6 is a functional coreceptor for primary isolates of human immunodeficiency virus type 1 (HIV-1) and HIV-2 on astrocytes

Stuart J D Neil et al. J Virol. 2005 Aug.

Abstract

The role of coreceptors other than CCR5 and CXCR4 in the pathogenesis of human immunodeficiency virus (HIV) disease is controversial. Here we show that a promiscuous CC chemokine receptor, D6, can function as a coreceptor for various primary dual-tropic isolates of HIV type 1 (HIV-1) and HIV-2. Furthermore, D6 usage is common among chimeric HIV-1 constructs bearing the gp120 proteins of isolates from early seroconverting patients. D6 mRNA and immunoreactivity were demonstrated to be expressed in HIV-1 target cells such as macrophages, peripheral blood mononuclear cells, and primary astrocytes. In primary astrocytes, an RNA interference-mediated knockdown of D6 expression inhibited D6-tropic isolate infection. D6 usage may account for some previous observations of alternative receptor tropism for primary human cells. Thus, D6 may be an important receptor for HIV pathogenesis in the brain and for the early dissemination of virus in the host.

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Figures

FIG. 1.
FIG. 1.
D6 as a functional chemokine receptor for primary isolates of HIV-1 (A) and HIV-2 (B). Viruses were titrated on NP2/CD4 cells overexpressing no chemokine receptor, D6, CXCR4, or CCR5 and stained in situ for viral antigen expression at 72 h postinfection. Titers are expressed in focus-forming units (FFU)/ml.
FIG. 2.
FIG. 2.
Blockade of D6-mediated infection of NP2/CD4/D6 cells. (A) HIV-1 Han2 was used to infect NP2/CD4/D6 cells in the presence of the indicated concentrations of human recombinant chemokines. Infection is expressed as a percentage of the titer of the virus on untreated NP2/CD4/D6 cells. (B) Blockade of HIV-1 Han2 using 5 μg polyclonal anti-human D6 antibody, processed as described for panel A. (C) Titers of HIV-1 Han2 on NP2/CD4/D6 cells transfected or mock transfected with siRNA oligonucleotides directed against the coding sequence of the D6 cDNA (si1 and si2) or the 3′ untranslated region of the mature D6 mRNA that is not contained within the expression cassette. Titers are expressed in FFU/ml. All error bars represent standard deviations of the means of three experiments.
FIG. 3.
FIG. 3.
D6 is a coreceptor for viral envelopes derived from early seroconvertors. Titration was performed with HIV-1 HXB2 molecular clones encoding the gp120 proteins of viruses derived from early seroconvertors. Recombinant viruses were titrated on NP2/CD4 cells expressing CD4 alone or in combination with D6, CCR5, or CXCR4.
FIG. 4.
FIG. 4.
D6 expression on primary HIV target cells. (A) RT-PCR for D6 mRNA in primary human astrocytes (lanes 1), brain microvascular endothelial cells (lanes 2), and primary macrophages (lanes 3). Cellular glyceraldehyde-3-phosphate dehydrogenase mRNA served as a control for reverse transcription reactions with or without the RT enzyme. (B) Flow cytometry for D6 surface expression. Control goat immunoglobulin G (solid peaks) or polyclonal goat anti-human D6 was used to stain NP2/CD4/D6 cells, primary human macrophages, primary adult astrocytes, and stimulated human PBMC cultures costained with a CD14 or CD4 monoclonal antibody conjugated to fluorescein isothiocyanate. D6 expression was revealed with a secondary anti-goat phycoerythrin-conjugated antibody.
FIG. 5.
FIG. 5.
D6 is a functional coreceptor on primary human astrocytes. (A) HIV-1 and HIV-2 primary isolates and recombinant viruses bearing seroconvertor envelopes were titrated on primary adult astrocyte 001A cultures that were preexposed or not to an adenoviral vector encoding human CD4. Cells were fixed and stained at 72 h postinfection. (B) siRNA-mediated knockdown of D6 in human astrocytes. Astrocyte cultures 001A and 003 were transfected with D6 siRNAs (1:1:1 [si1:si2:si3]) or an irrelevant siRNA. Five days later, the cells were replated and transduced with Ad-CD4 overnight, and the indicated viruses were titrated on them and processed as described above. The results are expressed as percentages of infection compared to mock-transfected astrocytes. Error bars represent standard deviations for three experiments. (C) RNAi-treated astrocytes were infected with a VSV-G pseudotyped HIV-1-based vector encoding GFP. At 48 h posttransduction, GFP-positive colonies were enumerated by florescence microscopy. (D) Flow cytometric analysis of surface expression of D6 on 003 astrocytes 5 days after transfection with an irrelevant siRNA or D6 siRNA compared to D6 expression on untransfected cells (solid peaks).
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References

    1. Aasa-Chapman, M. M., A. Hayman, P. Newton, D. Cornforth, I. Williams, P. Borrow, P. Balfe, and A. McKnight. 2004. Development of the antibody response in acute HIV-1 infection. AIDS 18:371-381. - PubMed
    1. Al-Harthi, L., L. J. Guilbert, J. A. Hoxie, and A. Landay. 2002. Trophoblasts are productively infected by CD4-independent isolate of HIV type 1. AIDS Res. Hum. Retrovir. 18:13-17. - PubMed
    1. Alkhatib, G., C. Combadiere, C. C. Broder, Y. Feng, P. E. Kennedy, P. M. Murphy, and E. A. Berger. 1996. CC CKR5: a RANTES, MIP-1alpha, MIP-1beta receptor as a fusion cofactor for macrophage-tropic HIV-1. Science 272:1955-1958. - PubMed
    1. Bacsi, A., E. Csoma, Z. Beck, I. Andirko, J. Konya, L. Gergely, and F. D. Toth. 2001. Induction of HIV-1 replication in latently infected syncytiotrophoblast cells by contact with placental macrophages: role of interleukin-6 and tumor necrosis factor-alpha. J. Interferon Cytokine Res. 21:1079-1088. - PubMed
    1. Bissel, S. J., and C. A. Wiley. 2004. Human immunodeficiency virus infection of the brain: pitfalls in evaluating infected/affected cell populations. Brain Pathol. 14:97-108. - PMC - PubMed

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