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Sensing of HIV-1 Entry Triggers a Type I Interferon Response in Human Primary Macrophages.

ABSTRACT: Along with CD4⁺ T lymphocytes, macrophages are a major cellular source of HIV-1 replication and a potential viral reservoir. Following entry and reverse transcription in macrophages, cloaking of the viral cDNA by the HIV-1 capsid limits its cytosolic detection, enabling efficient replication. However, whether incoming HIV-1 particles are sensed by macrophages prior to reverse transcription remains unclear. Here, we show that HIV-1 triggers a broad expression of interferon (IFN)-stimulated genes (ISG) in monocyte-derived macrophages within a few hours after infection. This response does not require viral reverse transcription or the presence of HIV-1 RNA within particles, but viral fusion is essential. This response is elicited by viruses carrying different envelope proteins and thus different receptors to proceed for viral entry. Expression of ISG in response to viral entry requires TBK1 activity and type I IFNs signaling. Remarkably, the ISG response is transient but affects subsequent viral spread. Together, our results shed light on an early step of HIV-1 sensing by macrophages at the level of entry, which confers an early protection through type I IFN signaling and has potential implications in controlling the infection.IMPORTANCE HIV infection is restricted to T lymphocytes and macrophages. HIV-1-infected macrophages are found in many tissues of infected patients, even under antiretroviral therapy, and are considered a viral reservoir. How HIV-1 is detected and what type of responses are elicited upon sensing remain in great part elusive. The kinetics and localization of the production of cytokines such as interferons in response to HIV is of critical importance to understanding how the infection and the immune response are established. Our study provides evidence that macrophages can detect HIV-1 as soon as it enters the cell. Interestingly, this sensing is independent of the presence of viral nucleic acids within the particles but requires their fusion with the macrophages. This triggers a low interferon response, which activates an antiviral program protecting cells against further viral challenge and thus potentially limiting the spread of the infection.

SUBMITTER: Decalf J

PROVIDER: S-EPMC5512232 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Sensing of HIV-1 Entry Triggers a Type I Interferon Response in Human Primary Macrophages.

Decalf Jérémie J Desdouits Marion M Rodrigues Vasco V Gobert François-Xavier FX Gentili Matteo M Marques-Ladeira Santy S Chamontin Célia C Mougel Marylène M Cunha de Alencar Bruna B Benaroch Philippe P

Journal of virology 20170712 15

Along with CD4<sup>+</sup> T lymphocytes, macrophages are a major cellular source of HIV-1 replication and a potential viral reservoir. Following entry and reverse transcription in macrophages, cloaking of the viral cDNA by the HIV-1 capsid limits its cytosolic detection, enabling efficient replication. However, whether incoming HIV-1 particles are sensed by macrophages prior to reverse transcription remains unclear. Here, we show that HIV-1 triggers a broad expression of interferon (IFN)-stimul ...[more]

PMID: 28490595

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Project description:HIV is able to outpace the innate immune response, including the response mediated by interferon (IFN), to establish a productive infection. However, monocyte derived macrophages (MDMs) may be protected from HIV infection by treatment with type I IFN before virus exposure. The ability of HIV to modulate the type I IFN-mediated innate immune response when it encounters a cell that has already been exposed to IFN was investigated. To investigate the presence of HIV on an established IFN response, MDMs were subjected to four different conditions: (1) IFN-treated only, (2) IFN-treated followed by HIV infection, (3) HIV infected only, and (4) a mock-treated and mock-infected control. Microarray gene expression analysis was performed on a total of 24 samples derived from the 4 conditions assessed at 3 time points (1, 4 and 8 days following treatment/infection) for both IFN-α2 or -ω. Initially, ISGs were identified as those that were upregulated greater than 2-fold by IFN alone (condition 1) at both Days 4 and 8. Then, the IFN-treated condition was compared to the IFN-treated followed by HIV-infection condition in order to identify those ISGs that were downregulated at least 1.5-fold by the presence of HIV at both days. Assuming that it would be counterproductive for HIV infection by itself to induce the expression of ISGs with putative anti-HIV effects, those ISGs that were upregulated greater than 2-fold in the HIV control were removed. Finally, ISGs that passed these filters and were concordant with both IFN-treatments (IFN-α2 and -ω) were identified and corresponded to the following 8 ISGs: AXL receptor tyrosine kinase (AXL), interferon-alpha inducible protein 27 (IFI27), interferon-induced protein 44 (IFI44), interferon-induced protein 44-like (IFI44L), ISG15, OAS1, OAS3 and XIAP associated factor 1 (XAF1). It should be noted that the IFN-α2 and -ω microarray experiments were performed in different batches but batch effects were not corrected since genes were identified by the filtering approach just described within each batch.

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Dataset Information

Sensing of HIV-1 Entry Triggers a Type I Interferon Response in Human Primary Macrophages.

Publications

Sensing of HIV-1 Entry Triggers a Type I Interferon Response in Human Primary Macrophages.

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