1
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Sumner RP, Blest H, Lin M, Maluquer de Motes C, Towers GJ. HIV-1 with gag processing defects activates cGAS sensing. Retrovirology 2024; 21:10. [PMID: 38778414 PMCID: PMC11112816 DOI: 10.1186/s12977-024-00643-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND Detection of viruses by host pattern recognition receptors induces the expression of type I interferon (IFN) and IFN-stimulated genes (ISGs), which suppress viral replication. Numerous studies have described HIV-1 as a poor activator of innate immunity in vitro. The exact role that the viral capsid plays in this immune evasion is not fully understood. RESULTS To better understand the role of the HIV-1 capsid in sensing we tested the effect of making HIV-1 by co-expressing a truncated Gag that encodes the first 107 amino acids of capsid fused with luciferase or GFP, alongside wild type Gag-pol. We found that unlike wild type HIV-1, viral particles produced with a mixture of wild type and truncated Gag fused to luciferase or GFP induced a potent IFN response in THP-1 cells and macrophages. Innate immune activation by Gag-fusion HIV-1 was dependent on reverse transcription and DNA sensor cGAS, suggesting activation of an IFN response by viral DNA. Further investigation revealed incorporation of the Gag-luciferase/GFP fusion proteins into viral particles that correlated with subtle defects in wild type Gag cleavage and a diminished capacity to saturate restriction factor TRIM5α, likely due to aberrant particle formation. We propose that expression of the Gag fusion protein disturbs the correct cleavage and maturation of wild type Gag, yielding viral particles that are unable to effectively shield viral DNA from detection by innate sensors including cGAS. CONCLUSIONS These data highlight the crucial role of capsid in innate evasion and support growing literature that disruption of Gag cleavage and capsid formation induces a viral DNA- and cGAS-dependent innate immune response. Together these data demonstrate a protective role for capsid and suggest that antiviral activity of capsid-targeting antivirals may benefit from enhanced innate and adaptive immunity in vivo.
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Affiliation(s)
- Rebecca P Sumner
- Division of Infection and Immunity, University College London, 90 Gower Street, London, WC1E 6BT, UK.
- Department of Microbial Sciences, University of Surrey, Guildford, GU2 7XH, UK.
| | - Henry Blest
- Division of Infection and Immunity, University College London, 90 Gower Street, London, WC1E 6BT, UK
| | - Meiyin Lin
- Division of Infection and Immunity, University College London, 90 Gower Street, London, WC1E 6BT, UK
| | | | - Greg J Towers
- Division of Infection and Immunity, University College London, 90 Gower Street, London, WC1E 6BT, UK
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2
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Kaygisiz K, Rauch-Wirth L, Iscen A, Hartenfels J, Kremer K, Münch J, Synatschke CV, Weil T. Peptide Amphiphiles as Biodegradable Adjuvants for Efficient Retroviral Gene Delivery. Adv Healthc Mater 2024; 13:e2301364. [PMID: 37947246 DOI: 10.1002/adhm.202301364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 10/20/2023] [Indexed: 11/12/2023]
Abstract
Retroviral gene delivery is the key technique for in vitro and ex vivo gene therapy. However, inefficient virion-cell attachment resulting in low gene transduction efficacy remains a major challenge in clinical applications. Adjuvants for ex vivo therapy settings need to increase transduction efficiency while being easily removed or degraded post-transduction to prevent the risk of venous embolism after infusing the transduced cells back to the bloodstream of patients, yet no such peptide system have been reported thus far. In this study, peptide amphiphiles (PAs) with a hydrophobic fatty acid and a hydrophilic peptide moiety that reveal enhanced viral transduction efficiency are introduced. The PAs form β-sheet-rich fibrils that assemble into positively charged aggregates, promoting virus adhesion to the cell membrane. The block-type amphiphilic sequence arrangement in the PAs ensures efficient cell-virus interaction and biodegradability. Good biodegradability is observed for fibrils forming small aggregates and it is shown that via molecular dynamics simulations, the fibril-fibril interactions of PAs are governed by fibril surface hydrophobicity. These findings establish PAs as additives in retroviral gene transfer, rivalling commercially available transduction enhancers in efficiency and degradability with promising translational options in clinical gene therapy applications.
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Affiliation(s)
- Kübra Kaygisiz
- Department Synthesis of Macromolecules, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Lena Rauch-Wirth
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstraße 1, 89081, Ulm, Germany
| | - Aysenur Iscen
- Polymer Theory Department, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Jan Hartenfels
- Department Synthesis of Macromolecules, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Kurt Kremer
- Polymer Theory Department, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Jan Münch
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstraße 1, 89081, Ulm, Germany
| | - Christopher V Synatschke
- Department Synthesis of Macromolecules, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Tanja Weil
- Department Synthesis of Macromolecules, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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3
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Tripathi A, Iyer K, Mitra D. HIV-1 replication requires optimal activation of the unfolded protein response. FEBS Lett 2023; 597:2908-2930. [PMID: 37984889 DOI: 10.1002/1873-3468.14772] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/16/2023] [Accepted: 10/29/2023] [Indexed: 11/22/2023]
Abstract
Several human diseases including viral infections activate the unfolded protein response (UPR) due to abnormal accumulation of unfolded/misfolded proteins. However, UPR modulation and its functional relevance in HIV-1 infection lack comprehensive elucidation. This study reveals that HIV-1 activates IRE1, PERK, and ATF6 signaling pathways of UPR. The knockdown of PERK and ATF6 reduces HIV-1 long terminal repeat (LTR)-driven gene expression, whereas the endoplasmic reticulum (ER) chaperone HSPA5 prevents proteasomal degradation of HIV-1 p24 through its chaperone activity. Interestingly, overstimulation of UPR by a chemical inducer leads to anti-HIV activity through an enhanced type-1 interferon response. Also, treatment with a chemical ER stress inhibitor reduces HIV-1 replication. These findings suggest that an optimal UPR activation is crucial for effective viral replication, as either overstimulating UPR or inhibiting ER stress leads to viral suppression.
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4
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Pagani I, Demela P, Ghezzi S, Vicenzi E, Pizzato M, Poli G. Host Restriction Factors Modulating HIV Latency and Replication in Macrophages. Int J Mol Sci 2022; 23:ijms23063021. [PMID: 35328442 PMCID: PMC8951319 DOI: 10.3390/ijms23063021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 03/06/2022] [Accepted: 03/07/2022] [Indexed: 12/15/2022] Open
Abstract
In addition to CD4+ T lymphocytes, myeloid cells and, particularly, differentiated macrophages are targets of human immunodeficiency virus type-1 (HIV-1) infection via the interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication, although with substantial differences. In contrast to activated CD4+ T lymphocytes, HIV-1 replication in macrophages occurs in nondividing cells and it is characterized by the virtual absence of cytopathicity both in vitro and in vivo. These general features should be considered in evaluating the role of cell-associated restriction factors aiming at preventing or curtailing virus replication in macrophages and T cells, particularly in the context of designing strategies to tackle the viral reservoir in infected individuals receiving combination antiretroviral therapy. In this regard, we will here also discuss a model of reversible HIV-1 latency in primary human macrophages and the role of host factors determining the restriction or reactivation of virus replication in these cells.
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Affiliation(s)
- Isabel Pagani
- Viral Pathogenesis and Biosafety Unit, San Raffaele Scientific Institute, Via Olgettina n. 58, 20132 Milano, Italy; (I.P.); (S.G.); (E.V.)
| | - Pietro Demela
- Human Immuno-Virology Unit, San Raffaele Scientific Institute, Via Olgettina n. 58, 20132 Milano, Italy;
| | - Silvia Ghezzi
- Viral Pathogenesis and Biosafety Unit, San Raffaele Scientific Institute, Via Olgettina n. 58, 20132 Milano, Italy; (I.P.); (S.G.); (E.V.)
| | - Elisa Vicenzi
- Viral Pathogenesis and Biosafety Unit, San Raffaele Scientific Institute, Via Olgettina n. 58, 20132 Milano, Italy; (I.P.); (S.G.); (E.V.)
| | - Massimo Pizzato
- Department of Cellular, Computational and Integrative Biology, University of Trento, 38123 Trento, Italy;
| | - Guido Poli
- Human Immuno-Virology Unit, San Raffaele Scientific Institute, Via Olgettina n. 58, 20132 Milano, Italy;
- School of Medicine, Vita-Salute San Raffaele University, Via Olgettina n. 58, 20132 Milano, Italy
- Correspondence: ; Tel.: +39-02-2643-4909
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5
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Toll-Like Receptor (TLR) Signaling Enables Cyclic GMP-AMP Synthase (cGAS) Sensing of HIV-1 Infection in Macrophages. mBio 2021; 12:e0281721. [PMID: 34844429 PMCID: PMC8630538 DOI: 10.1128/mbio.02817-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
HIV-1 replicates in cells that express a wide array of innate immune sensors and may do so simultaneously with other pathogens. How a coexisting innate immune stimulus influences the outcome of HIV-1 sensing, however, remains poorly understood. Here, we demonstrate that the activation of a second signaling pathway enables a cyclic GMP-AMP synthase (cGAS)-dependent type I interferon (IFN-I) response to HIV-1 infection. We used RNA sequencing to determine that HIV-1 alone induced few or no signs of an IFN-I response in THP-1 cells. In contrast, when supplemented with suboptimal levels of bacterial lipopolysaccharide (LPS), HIV-1 infection triggered the production of elevated levels of IFN-I and significant upregulation of interferon-stimulated genes. LPS-mediated enhancement of IFN-I production upon HIV-1 infection, which was observed in primary macrophages, was lost by blocking reverse transcription and with a hyperstable capsid, pointing to viral DNA being an essential immunostimulatory molecule. LPS also synergistically enhanced IFN-I production by cyclic GMP-AMP (cGAMP), a second messenger of cGAS. These observations suggest that the DNA sensor cGAS is responsible for a type I IFN response to HIV-1 in concert with LPS receptor Toll-like receptor 4 (TLR4). Small amounts of a TLR2 agonist also cooperate with HIV-1 to induce type I IFN production. These results demonstrate how subtle immunomodulatory activity renders HIV-1 capable of eliciting an IFN-I response through positive cross talk between cGAS and TLR sensing pathways.
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6
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Wiche Salinas TR, Gosselin A, Raymond Marchand L, Moreira Gabriel E, Tastet O, Goulet JP, Zhang Y, Vlad D, Touil H, Routy JP, Bego MG, El-Far M, Chomont N, Landay AL, Cohen ÉA, Tremblay C, Ancuta P. IL-17A reprograms intestinal epithelial cells to facilitate HIV-1 replication and outgrowth in CD4+ T cells. iScience 2021; 24:103225. [PMID: 34712922 PMCID: PMC8531570 DOI: 10.1016/j.isci.2021.103225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 08/09/2021] [Accepted: 10/01/2021] [Indexed: 12/25/2022] Open
Abstract
The crosstalk between intestinal epithelial cells (IECs) and Th17-polarized CD4+ T cells is critical for mucosal homeostasis, with HIV-1 causing significant alterations in people living with HIV (PLWH) despite antiretroviral therapy (ART). In a model of IEC and T cell co-cultures, we investigated the effects of IL-17A, the Th17 hallmark cytokine, on IEC ability to promote de novo HIV infection and viral reservoir reactivation. Our results demonstrate that IL-17A acts in synergy with TNF to boost IEC production of CCL20, a Th17-attractant chemokine, and promote HIV trans-infection of CD4+ T cells and viral outgrowth from reservoir cells of ART-treated PLWH. Importantly, the Illumina RNA-sequencing revealed an IL-17A-mediated pro-inflammatory and pro-viral molecular signature, including a decreased expression of type I interferon (IFN-I)-induced HIV restriction factors. These findings point to the deleterious features of IL-17A and raise awareness for caution when designing therapies aimed at restoring the paucity of mucosal Th17 cells in ART-treated PLWH. IL-17A acts in synergy with TNF to enhance CCL20 production in IEC exposed to HIV IL-17A/TNF-activated IEC efficiently promote HIV trans-infection of CD4+ T cells IL-17A reprograms IEC to boost HIV outgrowth from CD4+ T cells of ART-treated PLWH IL-17A decreases the expression of IFN-I-induced HIV restriction factors in IEC
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Affiliation(s)
- Tomas Raul Wiche Salinas
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
| | - Annie Gosselin
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
| | | | - Etiene Moreira Gabriel
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
| | - Olivier Tastet
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
| | | | - Yuwei Zhang
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
| | - Dragos Vlad
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
| | - Hanane Touil
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
| | - Jean-Pierre Routy
- Chronic Viral Illness Service and Division of Hematology, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Mariana G. Bego
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
- Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
| | - Mohamed El-Far
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
| | - Nicolas Chomont
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
| | - Alan L. Landay
- Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Éric A. Cohen
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
- Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada
| | - Cécile Tremblay
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
| | - Petronela Ancuta
- CHUM-Research Centre, 900 rue Saint-Denis, Tour Viger R, room R09.416, Montreal, QC H2X 0A9, Canada
- Département de microbiologie, infectiologie et immunologie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada
- Corresponding author
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7
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Bauby H, Ward CC, Hugh-White R, Swanson CM, Schulz R, Goujon C, Malim MH. HIV-1 Vpr Induces Widespread Transcriptomic Changes in CD4 + T Cells Early Postinfection. mBio 2021; 12:e0136921. [PMID: 34154423 PMCID: PMC8263007 DOI: 10.1128/mbio.01369-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 05/19/2021] [Indexed: 12/12/2022] Open
Abstract
The interactions between a virus and its host are complex but can be broadly categorized as either viral manipulation of cellular functions or cellular responses to infection. These processes begin at the earliest point of contact between virus and cell and frequently result in changes to cellular gene expression, making genome-wide transcriptomics a useful tool to study them. Several previous studies have used transcriptomics to evaluate the cellular responses to human immunodeficiency virus type 1 (HIV-1) infection; however, none have examined events in primary CD4+ T cells during the first 24 h of infection. Here, we analyzed CD4+ T cells at 4.5, 8, 12, 24, and 48 h following infection. We describe global changes to host gene expression commencing at 4.5 h postinfection and evolving over the ensuing time points. We identify upregulation of genes related to innate immunity, cytokine production, and apoptosis and downregulation of those involved in transcription and translation. We further demonstrate that the viral accessory protein Vpr is necessary for almost all gene expression changes seen at 12 h postinfection and the majority of those seen at 48 h. Identifying this new role for Vpr not only provides fresh perspective on its possible function but also adds further insight into the interplay between HIV-1 and its host at the cellular level. IMPORTANCE HIV-1, while now treatable, remains an important human pathogen causing significant morbidity and mortality globally. The virus predominantly infects CD4+ T cells and, if not treated with medication, ultimately causes their depletion, resulting in AIDS and death. Further refining our understanding of the interaction between HIV-1 and these cells has the potential to inform further therapeutic development. Previous studies have used transcriptomics to assess gene expression changes in CD4+ T cells following HIV-1 infection; here, we provide a detailed examination of changes occurring in the first 24 h of infection. Importantly, we define the viral protein Vpr as essential for the changes observed at this early stage. This finding has significance for understanding the role of Vpr in infection and pathogenesis and also for interpreting previous transcriptomic analyses of HIV-1 infection.
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Affiliation(s)
- Hélène Bauby
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Christopher C. Ward
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Rupert Hugh-White
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Chad M. Swanson
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Reiner Schulz
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Caroline Goujon
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Michael H. Malim
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
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8
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Müller TG, Zila V, Peters K, Schifferdecker S, Stanic M, Lucic B, Laketa V, Lusic M, Müller B, Kräusslich HG. HIV-1 uncoating by release of viral cDNA from capsid-like structures in the nucleus of infected cells. eLife 2021; 10:64776. [PMID: 33904396 PMCID: PMC8169111 DOI: 10.7554/elife.64776] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 04/21/2021] [Indexed: 12/11/2022] Open
Abstract
HIV-1 replication commences inside the cone-shaped viral capsid, but timing, localization, and mechanism of uncoating are under debate. We adapted a strategy to visualize individual reverse-transcribed HIV-1 cDNA molecules and their association with viral and cellular proteins using fluorescence and correlative-light-and-electron-microscopy (CLEM). We specifically detected HIV-1 cDNA inside nuclei, but not in the cytoplasm. Nuclear cDNA initially co-localized with a fluorescent integrase fusion (IN-FP) and the viral CA (capsid) protein, but cDNA-punctae separated from IN-FP/CA over time. This phenotype was conserved in primary HIV-1 target cells, with nuclear HIV-1 complexes exhibiting strong CA-signals in all cell types. CLEM revealed cone-shaped HIV-1 capsid-like structures and apparently broken capsid-remnants at the position of IN-FP signals and elongated chromatin-like structures in the position of viral cDNA punctae lacking IN-FP. Our data argue for nuclear uncoating by physical disruption rather than cooperative disassembly of the CA-lattice, followed by physical separation from the pre-integration complex.
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Affiliation(s)
- Thorsten G Müller
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Vojtech Zila
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Kyra Peters
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Sandra Schifferdecker
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Mia Stanic
- Department of Infectious Diseases Integrative Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Bojana Lucic
- Department of Infectious Diseases Integrative Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Vibor Laketa
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infection Research, partner site Heidelberg, Heidelberg, Germany
| | - Marina Lusic
- Department of Infectious Diseases Integrative Virology, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infection Research, partner site Heidelberg, Heidelberg, Germany
| | - Barbara Müller
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Hans-Georg Kräusslich
- Department of Infectious Diseases Virology, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infection Research, partner site Heidelberg, Heidelberg, Germany
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9
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Khan H, Sumner RP, Rasaiyaah J, Tan CP, Rodriguez-Plata MT, Van Tulleken C, Fink D, Zuliani-Alvarez L, Thorne L, Stirling D, Milne RSB, Towers GJ. HIV-1 Vpr antagonizes innate immune activation by targeting karyopherin-mediated NF-κB/IRF3 nuclear transport. eLife 2020; 9:e60821. [PMID: 33300875 PMCID: PMC7759385 DOI: 10.7554/elife.60821] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 12/09/2020] [Indexed: 12/13/2022] Open
Abstract
HIV-1 must replicate in cells that are equipped to defend themselves from infection through intracellular innate immune systems. HIV-1 evades innate immune sensing through encapsidated DNA synthesis and encodes accessory genes that antagonize specific antiviral effectors. Here, we show that both particle associated, and expressed HIV-1 Vpr, antagonize the stimulatory effect of a variety of pathogen associated molecular patterns by inhibiting IRF3 and NF-κB nuclear transport. Phosphorylation of IRF3 at S396, but not S386, was also inhibited. We propose that, rather than promoting HIV-1 nuclear import, Vpr interacts with karyopherins to disturb their import of IRF3 and NF-κB to promote replication in macrophages. Concordantly, we demonstrate Vpr-dependent rescue of HIV-1 replication in human macrophages from inhibition by cGAMP, the product of activated cGAS. We propose a model that unifies Vpr manipulation of nuclear import and inhibition of innate immune activation to promote HIV-1 replication and transmission.
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Affiliation(s)
- Hataf Khan
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Rebecca P Sumner
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Jane Rasaiyaah
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Choon Ping Tan
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | | | - Chris Van Tulleken
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Douglas Fink
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | | | - Lucy Thorne
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - David Stirling
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Richard SB Milne
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | - Greg J Towers
- Division of Infection and Immunity, University College LondonLondonUnited Kingdom
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10
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Elsner C, Ponnurangam A, Kazmierski J, Zillinger T, Jansen J, Todt D, Döhner K, Xu S, Ducroux A, Kriedemann N, Malassa A, Larsen PK, Hartmann G, Barchet W, Steinmann E, Kalinke U, Sodeik B, Goffinet C. Absence of cGAS-mediated type I IFN responses in HIV-1-infected T cells. Proc Natl Acad Sci U S A 2020; 117:19475-19486. [PMID: 32709741 PMCID: PMC7431009 DOI: 10.1073/pnas.2002481117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The DNA sensor cGAS catalyzes the production of the cyclic dinucleotide cGAMP, resulting in type I interferon responses. We addressed the functionality of cGAS-mediated DNA sensing in human and murine T cells. Activated primary CD4+ T cells expressed cGAS and responded to plasmid DNA by upregulation of ISGs and release of bioactive interferon. In mouse T cells, cGAS KO ablated sensing of plasmid DNA, and TREX1 KO enabled cells to sense short immunostimulatory DNA. Expression of IFIT1 and MX2 was downregulated and upregulated in cGAS KO and TREX1 KO T cell lines, respectively, compared to parental cells. Despite their intact cGAS sensing pathway, human CD4+ T cells failed to mount a reverse transcriptase (RT) inhibitor-sensitive immune response following HIV-1 infection. In contrast, infection of human T cells with HSV-1 that is functionally deficient for the cGAS antagonist pUL41 (HSV-1ΔUL41N) resulted in a cGAS-dependent type I interferon response. In accordance with our results in primary CD4+ T cells, plasmid challenge or HSV-1ΔUL41N inoculation of T cell lines provoked an entirely cGAS-dependent type I interferon response, including IRF3 phosphorylation and expression of ISGs. In contrast, no RT-dependent interferon response was detected following transduction of T cell lines with VSV-G-pseudotyped lentiviral or gammaretroviral particles. Together, T cells are capable to raise a cGAS-dependent cell-intrinsic response to both plasmid DNA challenge or inoculation with HSV-1ΔUL41N. However, HIV-1 infection does not appear to trigger cGAS-mediated sensing of viral DNA in T cells, possibly by revealing viral DNA of insufficient quantity, length, and/or accessibility to cGAS.
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Affiliation(s)
- Carina Elsner
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
- Institute for Virology, University of Duisburg-Essen, University Hospital Essen, 45147 Essen, Germany
| | - Aparna Ponnurangam
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Julia Kazmierski
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
- Institute of Virology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
- Berlin Institute of Health, 10178 Berlin, Germany
| | - Thomas Zillinger
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital, University of Bonn, 53127 Bonn, Germany
| | - Jenny Jansen
- Institute of Virology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
- Berlin Institute of Health, 10178 Berlin, Germany
| | - Daniel Todt
- Department of Molecular and Medical Virology, Ruhr University Bochum, 44801 Bochum, Germany
- European Virus Bioinformatics Center, 07743 Jena, Germany
| | - Katinka Döhner
- Institute of Virology, Hanover Medical School, 30625 Hanover, Germany
| | - Shuting Xu
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Aurélie Ducroux
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Nils Kriedemann
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Angelina Malassa
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Pia-Katharina Larsen
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Gunther Hartmann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital, University of Bonn, 53127 Bonn, Germany
| | - Winfried Barchet
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital, University of Bonn, 53127 Bonn, Germany
- German Center for Infection Research, 50935 Cologne-Bonn, Germany
| | - Eike Steinmann
- Department of Molecular and Medical Virology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany
| | - Beate Sodeik
- Institute of Virology, Hanover Medical School, 30625 Hanover, Germany
- Cluster of Excellence Resolving Infection Susceptibility (Excellence Cluster 2155), Hanover Medical School, 30625 Hanover, Germany
| | - Christine Goffinet
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30625 Hanover, Germany;
- Institute of Virology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
- Berlin Institute of Health, 10178 Berlin, Germany
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11
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Tsopoulidis N, Kaw S, Laketa V, Kutscheidt S, Baarlink C, Stolp B, Grosse R, Fackler OT. T cell receptor-triggered nuclear actin network formation drives CD4 + T cell effector functions. Sci Immunol 2020; 4:4/31/eaav1987. [PMID: 30610013 DOI: 10.1126/sciimmunol.aav1987] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 11/26/2018] [Indexed: 12/24/2022]
Abstract
T cell antigen receptor (TCR) signaling triggers selective cytokine expression to drive T cell proliferation and differentiation required for immune defense and surveillance. The nuclear signaling events responsible for specificity in cytokine gene expression upon T cell activation are largely unknown. Here, we uncover formation of a dynamic actin filament network in the nucleus that regulates cytokine expression for effector functions of CD4+ T lymphocytes. TCR engagement triggers the rapid and transient formation of a nuclear actin filament network via nuclear Arp2/3 complex, induced by elevated nuclear Ca2+ levels and regulated via N-Wasp and NIK. Specific interference with TCR-induced formation of nuclear actin filaments impairs production of effector cytokines and prevents generation of antigen-specific antibodies but does not interfere with immune synapse formation and cell proliferation. Ca2+-regulated actin polymerization in the nucleus allows CD4+ T cells the rapid conversion of TCR signals into effector functions required for T cell help.
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Affiliation(s)
- N Tsopoulidis
- Department of Infectious Diseases, Integrative Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany.,Hartmut Hoffmann-Berling International Graduate School of Molecular and Cellular Biology (HBIGS), Heidelberg, Germany
| | - S Kaw
- Department of Infectious Diseases, Integrative Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany
| | - V Laketa
- Department of Infectious Diseases, Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infection Research, Partner Site Heidelberg, 69120 Heidelberg, Germany
| | - S Kutscheidt
- Department of Infectious Diseases, Integrative Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany
| | - C Baarlink
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
| | - B Stolp
- Department of Infectious Diseases, Integrative Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany
| | - R Grosse
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
| | - O T Fackler
- Department of Infectious Diseases, Integrative Virology, CIID, University Hospital Heidelberg, Heidelberg, Germany.
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12
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Farrants H, Tarnawski M, Müller TG, Otsuka S, Hiblot J, Koch B, Kueblbeck M, Kräusslich HG, Ellenberg J, Johnsson K. Chemogenetic Control of Nanobodies. Nat Methods 2020; 17:279-282. [PMID: 32066961 DOI: 10.1038/s41592-020-0746-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 12/01/2019] [Accepted: 01/15/2020] [Indexed: 12/30/2022]
Abstract
We introduce an engineered nanobody whose affinity to green fluorescent protein (GFP) can be switched on and off with small molecules. By controlling the cellular localization of GFP fusion proteins, the engineered nanobody allows interrogation of their roles in basic biological processes, an approach that should be applicable to numerous previously described GFP fusions. We also outline how the binding affinities of other nanobodies can be controlled by small molecules.
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Affiliation(s)
- Helen Farrants
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.,Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Miroslaw Tarnawski
- Protein Expression and Characterization Facility, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Thorsten G Müller
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Shotaro Otsuka
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.,Max Perutz Labs, a joint venture of the University of Vienna and the Medical University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Julien Hiblot
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Birgit Koch
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Moritz Kueblbeck
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Hans-Georg Kräusslich
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Jan Ellenberg
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Kai Johnsson
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany. .,Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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13
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HIV-2/SIV Vpx targets a novel functional domain of STING to selectively inhibit cGAS-STING-mediated NF-κB signalling. Nat Microbiol 2019; 4:2552-2564. [PMID: 31659299 DOI: 10.1038/s41564-019-0585-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 09/10/2019] [Indexed: 12/28/2022]
Abstract
Innate immunity is the first line of host defence against pathogens. Suppression of innate immune responses is essential for the survival of all viruses. However, the interplay between innate immunity and HIV/SIV is only poorly characterized. We have discovered Vpx as a novel inhibitor of innate immune activation that associates with STING signalosomes and interferes with the nuclear translocation of NF-κB and the induction of innate immune genes. This new function of Vpx could be separated from its role in mediating degradation of the antiviral factor SAMHD1, and is conserved among diverse HIV-2/SIV Vpx. Vpx selectively suppressed cGAS-STING-mediated nuclear factor-κB signalling. Furthermore, Vpx and Vpr had complementary activities against cGAS-STING activity. Since SIVMAC lacking both Vpx and Vpr was less pathogenic than SIV deficient for Vpr or Vpx alone, suppression of innate immunity by HIV/SIV is probably a key pathogenic determinant, making it a promising target for intervention.
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14
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Ombinda-Lemboumba S, Malabi R, Lugongolo MY, Thobakgale L, Manoto SL, Mthunzi-Kufa P. Label-free differentiation of human immunodeficiency virus-1 infected from uninfected cells using transmission measurement. JOURNAL OF BIOPHOTONICS 2019; 12:e201800349. [PMID: 30811866 DOI: 10.1002/jbio.201800349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 02/21/2019] [Accepted: 02/25/2019] [Indexed: 06/09/2023]
Abstract
Transmission measurement has been perceived as a potential candidate for label-free investigation of biological material. It is a real-time, label-free and non-invasive optical detection technique that has found wide applications in pharmaceutical industry as well as the biological and medical fields. Combining transmission measurement with optical trapping has emerged as a powerful tool allowing stable sample trapping, while also facilitating transmittance data analysis. In this study, a near-infrared laser beam emitting at a wavelength of 1064 nm was used for both optical trapping and transmission measurement investigation of human immunodeficiency virus 1 (HIV-1) infected and uninfected TZM-bl cells. The measurements of the transmittance intensity of individual cells in solution were carried out using a home built optical trapping system combined with laser transmission setup using a single beam gradient trap. Transmittance spectral intensity patterns revealed significant differences between the HIV-1 infected and uninfected cells. This result suggests that the transmittance data analysis technique used in this study has the potential to differentiate between infected and uninfected TZM-bl cells without the use of labels. The results obtained in this study could pave a way into developing an HIV-1 label-free diagnostic tool with possible applications at the point of care .
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Affiliation(s)
- Saturnin Ombinda-Lemboumba
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - Rudzani Malabi
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
- Department of Physics, University of South Africa, Florida, South Africa
| | - Masixole Y Lugongolo
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
- Department of Physics, University of South Africa, Florida, South Africa
| | - Lebogang Thobakgale
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - Sello L Manoto
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - Patience Mthunzi-Kufa
- Biophotonics, National Laser Centre, Council for Scientific and Industrial Research, Pretoria, South Africa
- Department of Physics, University of South Africa, Florida, South Africa
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15
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Herrera C. The Pre-clinical Toolbox of Pharmacokinetics and Pharmacodynamics: in vitro and ex vivo Models. Front Pharmacol 2019; 10:578. [PMID: 31178736 PMCID: PMC6543330 DOI: 10.3389/fphar.2019.00578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 05/06/2019] [Indexed: 01/05/2023] Open
Abstract
Prevention strategies against sexual transmission of human immunodeficiency virus (HIV) are essential to curb the rate of new infections. In the absence of a correlate of protection against HIV infection, pre-clinical evaluation is fundamental to facilitate and accelerate prioritization of prevention candidates and their formulations in a rapidly evolving clinical landscape. Characterization of pharmacokinetic (PK) and pharmacodynamic (PD) properties for candidate inhibitors is the main objective of pre-clinical evaluation. in vitro and ex vivo systems for pharmacological assessment allow experimental flexibility and adaptability at a relatively low cost without raising as significant ethical concerns as in vivo models. Applications and limitations of pre-clinical PK/PD models and future alternatives are reviewed in the context of HIV prevention.
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Affiliation(s)
- Carolina Herrera
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
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16
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Chase AJ, Wombacher R, Fackler OT. Intrinsic properties and plasma membrane trafficking route of Src family kinase SH4 domains sensitive to retargeting by HIV-1 Nef. J Biol Chem 2018; 293:7824-7840. [PMID: 29588370 DOI: 10.1074/jbc.ra118.002794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Indexed: 01/18/2023] Open
Abstract
The HIV type 1 pathogenicity factor Nef enhances viral replication by modulating multiple host cell pathways, including tuning the activation state of infected CD4 T lymphocytes to optimize virus spread. For this, Nef inhibits anterograde transport of the Src family kinase (SFK) Lck toward the plasma membrane (PM). This leads to retargeting of the kinase to the trans-Golgi network, whereas the intracellular transport of a related SFK, Fyn, is unaffected by Nef. The 18-amino acid Src homology 4 (SH4) domain membrane anchor of Lck is necessary and sufficient for Nef-mediated retargeting, but other details of this process are not known. The goal of this study was therefore to identify characteristics of SH4 domains responsive to Nef and the transport machinery used. Screening a panel of SFK SH4 domains revealed two groups that were sensitive or insensitive for trans-Golgi network retargeting by Nef as well as the importance of the amino acid at position 8 for determining Nef sensitivity. Anterograde transport of Nef-sensitive domains was characterized by slower delivery to the PM and initial targeting to Golgi membranes, where transport was arrested in the presence of Nef. For Nef-sensitive SH4 domains, ectopic expression of the lipoprotein binding chaperone Unc119a or the GTPase Arl3 or reduction of their endogenous expression phenocopied the effect of Nef. Together, these results suggest that, analogous to K-Ras, Nef-sensitive SH4 domains are transported to the PM by a cycle of solubilization and membrane insertion and that intrinsic properties define SH4 domains as cargo of this Nef-sensitive lipoprotein binding chaperone-GTPase transport cycle.
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Affiliation(s)
- Amanda J Chase
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Rebecka Wombacher
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Oliver T Fackler
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
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17
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Francica BJ, Ghasemzadeh A, Desbien AL, Theodros D, Sivick KE, Reiner GL, Hix Glickman L, Marciscano AE, Sharabi AB, Leong ML, McWhirter SM, Dubensky TW, Pardoll DM, Drake CG. TNFα and Radioresistant Stromal Cells Are Essential for Therapeutic Efficacy of Cyclic Dinucleotide STING Agonists in Nonimmunogenic Tumors. Cancer Immunol Res 2018; 6:422-433. [PMID: 29472271 DOI: 10.1158/2326-6066.cir-17-0263] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 10/03/2017] [Accepted: 02/07/2018] [Indexed: 12/20/2022]
Abstract
The cGAS-STING cytosolic DNA sensing pathway may play an integral role in the initiation of antitumor immune responses. Studies evaluating the immunogenicity of various cyclic dinucleotide (CDN) STING agonists administered by intratumoral (i.t.) injection showed potent induction of inflammation, tumor necrosis, and, in some cases, durable tumor-specific adaptive immunity. However, the specific immune mechanisms underlying these responses remain incompletely defined. The majority of these studies have focused on the effect of CDNs on immune cells but have not conclusively interrogated the role of stromal cells in the acute rejection of the CDN-injected tumor. Here, we revealed a mechanism of STING agonist-mediated tumor response that relied on both stromal and immune cells to achieve tumor regression and clearance. Using knockout and bone marrow chimeric mice, we showed that although bone marrow-derived TNFα was necessary for CDN-induced necrosis, STING signaling in radioresistant stromal cells was also essential for CDN-mediated tumor rejection. These results provide evidence for crosstalk between stromal and hematopoietic cells during CDN-mediated tumor collapse after i.t. administration. These mechanistic insights may prove critical in the clinical development of STING agonists. Cancer Immunol Res; 6(4); 422-33. ©2018 AACR.
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Affiliation(s)
- Brian J Francica
- Aduro Biotech, Berkeley, California
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ali Ghasemzadeh
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Medicine, Division of Hematology/Oncology, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York
| | | | - Debebe Theodros
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | | | | | - Ariel E Marciscano
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Andrew B Sharabi
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
- University of California San Diego School of Medicine, San Diego, California
| | | | | | | | - Drew M Pardoll
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Charles G Drake
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland.
- Department of Medicine, Division of Hematology/Oncology, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York
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18
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Vermeire J, Roesch F, Sauter D, Rua R, Hotter D, Van Nuffel A, Vanderstraeten H, Naessens E, Iannucci V, Landi A, Witkowski W, Baeyens A, Kirchhoff F, Verhasselt B. HIV Triggers a cGAS-Dependent, Vpu- and Vpr-Regulated Type I Interferon Response in CD4 + T Cells. Cell Rep 2017; 17:413-424. [PMID: 27705790 DOI: 10.1016/j.celrep.2016.09.023] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/18/2016] [Accepted: 09/08/2016] [Indexed: 02/07/2023] Open
Abstract
Several pattern-recognition receptors sense HIV-1 replication products and induce type I interferon (IFN-I) production under specific experimental conditions. However, it is thought that viral sensing and IFN induction are virtually absent in the main target cells of HIV-1 in vivo. Here, we show that activated CD4+ T cells sense HIV-1 infection through the cytosolic DNA sensor cGAS and mount a bioactive IFN-I response. Efficient induction of IFN-I by HIV-1 infection requires proviral integration and is regulated by newly expressed viral accessory proteins: Vpr potentiates, while Vpu suppresses cGAS-dependent IFN-I induction. Furthermore, Vpr also amplifies innate sensing of HIV-1 infection in Vpx-treated dendritic cells. Our results identify cGAS as mediator of an IFN-I response to HIV-1 infection in CD4+ T cells and demonstrate that this response is modulated by the viral accessory proteins Vpr and Vpu. Thus, viral innate immune evasion is incomplete in the main target cells of HIV-1.
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Affiliation(s)
- Jolien Vermeire
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Ferdinand Roesch
- Département de Virologie, Unité Virus et Immunité, Institut Pasteur, 75015 Paris, France
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Réjane Rua
- Département de Virologie, Unité Virus et Immunité, Institut Pasteur, 75015 Paris, France
| | - Dominik Hotter
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Anouk Van Nuffel
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Hanne Vanderstraeten
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Evelien Naessens
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Veronica Iannucci
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Alessia Landi
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Wojciech Witkowski
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Ann Baeyens
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Bruno Verhasselt
- Department of Clinical Chemistry, Microbiology, and Immunology, Ghent University, 9000 Ghent, Belgium.
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19
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Sumner RP, Thorne LG, Fink DL, Khan H, Milne RS, Towers GJ. Are Evolution and the Intracellular Innate Immune System Key Determinants in HIV Transmission? Front Immunol 2017; 8:1246. [PMID: 29056936 PMCID: PMC5635324 DOI: 10.3389/fimmu.2017.01246] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/19/2017] [Indexed: 01/05/2023] Open
Abstract
HIV-1 is the single most important sexually transmitted disease in humans from a global health perspective. Among human lentiviruses, HIV-1 M group has uniquely achieved pandemic levels of human-to-human transmission. The requirement to transmit between hosts likely provides the strongest selective forces on a virus, as without transmission, there can be no new infections within a host population. Our perspective is that evolution of all of the virus-host interactions, which are inherited and perpetuated from host-to-host, must be consistent with transmission. For example, CXCR4 use, which often evolves late in infection, does not favor transmission and is therefore lost when a virus transmits to a new host. Thus, transmission inevitably influences all aspects of virus biology, including interactions with the innate immune system, and dictates the biological niche in which the virus exists in the host. A viable viral niche typically does not select features that disfavor transmission. The innate immune response represents a significant selective pressure during the transmission process. In fact, all viruses must antagonize and/or evade the mechanisms of the host innate and adaptive immune systems that they encounter. We believe that viewing host-virus interactions from a transmission perspective helps us understand the mechanistic details of antiviral immunity and viral escape. This is particularly true for the innate immune system, which typically acts from the very earliest stages of the host-virus interaction, and must be bypassed to achieve successful infection. With this in mind, here we review the innate sensing of HIV, the consequent downstream signaling cascades and the viral restriction that results. The centrality of these mechanisms to host defense is illustrated by the array of countermeasures that HIV deploys to escape them, despite the coding constraint of a 10 kb genome. We consider evasion strategies in detail, in particular the role of the HIV capsid and the viral accessory proteins highlighting important unanswered questions and discussing future perspectives.
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Affiliation(s)
- Rebecca P. Sumner
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Lucy G. Thorne
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Doug L. Fink
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Hataf Khan
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Richard S. Milne
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Greg J. Towers
- Division of Infection and Immunity, University College London, London, United Kingdom
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20
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Mücksch F, Laketa V, Müller B, Schultz C, Kräusslich HG. Synchronized HIV assembly by tunable PIP 2 changes reveals PIP 2 requirement for stable Gag anchoring. eLife 2017; 6. [PMID: 28574338 PMCID: PMC5495570 DOI: 10.7554/elife.25287] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 05/25/2017] [Indexed: 12/15/2022] Open
Abstract
HIV-1 assembles at the plasma membrane (PM) of infected cells. PM association of the main structural protein Gag depends on its myristoylated MA domain and PM PI(4,5)P2. Using a novel chemical biology tool that allows rapidly tunable manipulation of PI(4,5)P2 levels in living cells, we show that depletion of PI(4,5)P2 completely prevents Gag PM targeting and assembly site formation. Unexpectedly, PI(4,5)P2 depletion also caused loss of pre-assembled Gag lattices from the PM. Subsequent restoration of PM PI(4,5)P2 reinduced assembly site formation even in the absence of new protein synthesis, indicating that the dissociated Gag molecules remained assembly competent. These results reveal an important role of PI(4,5)P2 for HIV-1 morphogenesis beyond Gag recruitment to the PM and suggest a dynamic equilibrium of Gag-lipid interactions. Furthermore, they establish an experimental system that permits synchronized induction of HIV-1 assembly leading to induced production of infectious virions by targeted modulation of Gag PM targeting.
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Affiliation(s)
- Frauke Mücksch
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Vibor Laketa
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infectious Disease Research, Partner site Heidelberg, Braunschweig, Germany
| | - Barbara Müller
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Carsten Schultz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
| | - Hans-Georg Kräusslich
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany.,German Center for Infectious Disease Research, Partner site Heidelberg, Braunschweig, Germany
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21
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The murine cytomegalovirus M35 protein antagonizes type I IFN induction downstream of pattern recognition receptors by targeting NF-κB mediated transcription. PLoS Pathog 2017; 13:e1006382. [PMID: 28542326 PMCID: PMC5444856 DOI: 10.1371/journal.ppat.1006382] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 04/26/2017] [Indexed: 12/25/2022] Open
Abstract
The type I interferon (IFN) response is imperative for the establishment of the early antiviral immune response. Here we report the identification of the first type I IFN antagonist encoded by murine cytomegalovirus (MCMV) that shuts down signaling following pattern recognition receptor (PRR) sensing. Screening of an MCMV open reading frame (ORF) library identified M35 as a novel and strong negative modulator of IFNβ promoter induction following activation of both RNA and DNA cytoplasmic PRR. Additionally, M35 inhibits the proinflammatory cytokine response downstream of Toll-like receptors (TLR). Using a series of luciferase-based reporters with specific transcription factor binding sites, we determined that M35 targets NF-κB-, but not IRF-mediated, transcription. Expression of M35 upon retroviral transduction of immortalized bone marrow-derived macrophages (iBMDM) led to reduced IFNβ transcription and secretion upon activation of stimulator of IFN genes (STING)-dependent signaling. On the other hand, M35 does not antagonize interferon-stimulated gene (ISG) 56 promoter induction or ISG transcription upon exogenous stimulation of the type I IFN receptor (IFNAR). M35 is present in the viral particle and, upon MCMV infection of fibroblasts, is immediately shuttled to the nucleus where it exerts its immunomodulatory effects. Deletion of M35 from the MCMV genome and hence from the viral particle resulted in elevated type I IFN transcription and secretion in vitro and in vivo. In the absence of M35, lower viral titers are observed during acute infection of the host, and productive infection in the salivary glands was not detected. In conclusion, the M35 protein is released by MCMV immediately upon infection in order to deftly inhibit the antiviral type I IFN response by targeting NF-κB-mediated transcription. The identification of this novel viral protein reinforces the importance of timely countermeasures in the complex relationship between virus and host. The herpesvirus cytomegalovirus can cause severe morbidity in immunosuppressed people and poses a much greater global problem in the context of congenital infections than the Zika virus. To establish infection, cytomegalovirus needs to modulate the antiviral immune response of its host. One of the first lines of defense against viral infections is the type I interferon response which is activated by cellular sensors called pattern recognition receptors. These receptors sense viral entry and rapidly induce the transcription of type I interferons, which are instrumental for the induction of an antiviral state in infected and surrounding cells. We have identified the first viral protein encoded by murine cytomegalovirus, the M35 protein, that counteracts type I interferon transcription downstream of multiple pattern recognition receptors. We found that this viral countermeasure occurs shortly after viral entry into the host cell, as M35 is delivered with the viral particle. M35 then localizes to the nucleus where it modulates NF-κB-mediated transcription. In vivo, murine cytomegalovirus deficient of the M35 protein replicates to lower levels in spleen and liver and cannot establish a productive infection in the salivary glands, which is a key site of viral transmission, highlighting the important role of M35 for the establishment of infection. Our study provides novel insights into the complex interaction between cytomegalovirus and the innate immune response of its host.
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Conserved Interaction of Lentiviral Vif Molecules with HIV-1 Gag and Differential Effects of Species-Specific Vif on Virus Production. J Virol 2017; 91:JVI.00064-17. [PMID: 28122978 DOI: 10.1128/jvi.00064-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 01/05/2023] Open
Abstract
The virion infectivity factor (Vif) open reading frame is conserved among most lentiviruses. Vif molecules contribute to viral replication by inactivating host antiviral factors, the APOBEC3 cytidine deaminases. However, various species of lentiviral Vif proteins have evolved different strategies for overcoming host APOBEC3. Whether different species of lentiviral Vif proteins still preserve certain common features has not been reported. Here, we show for the first time that diverse lentiviral Vif molecules maintain the ability to interact with the human immunodeficiency virus type 1 (HIV-1) Gag precursor (Pr55Gag) polyprotein. Surprisingly, bovine immunodeficiency virus (BIV) Vif, but not HIV-1 Vif, interfered with HIV-1 production and viral infectivity even in the absence of APOBEC3. Further analysis revealed that BIV Vif demonstrated an enhanced interaction with Pr55Gag compared to that of HIV-1 Vif, and BIV Vif defective for the Pr55Gag interaction lost its ability to inhibit HIV-1. The C-terminal region of capsid (CA) and the p2 region of Pr55Gag, which are important for virus assembly and maturation, were involved in the interaction. Transduction of CD4+ T cells with BIV Vif blocked HIV-1 replication. Thus, the conserved Vif-Pr55Gag interaction provides a potential target for the future development of antiviral strategies.IMPORTANCE The conserved Vif accessory proteins of primate lentiviruses HIV-1, simian immunodeficiency virus (SIV), and BIV all form ubiquitin ligase complexes to target host antiviral APOBEC3 proteins for degradation, with different cellular requirements and using different molecular mechanisms. Here, we demonstrate that BIV Vif can interfere with HIV-1 Gag maturation and suppress HIV-1 replication through interaction with the precursor of the Gag (Pr55Gag) of HIV-1 in virus-producing cells. Moreover, the HIV-1 and SIV Vif proteins are conserved in terms of their interactions with HIV-1 Pr55Gag although HIV-1 Vif proteins bind Pr55Gag less efficiently than those of BIV Vif. Our research not only sheds new light on this feature of these conserved lentiviral Vif proteins but also provides a formerly unrecognized target for the development of antiviral strategies. Since increasing the Vif-Pr55Gag interaction could potentially suppress virus proliferation, this approach could offer a new strategy for the development of HIV inhibitors.
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González ME. The HIV-1 Vpr Protein: A Multifaceted Target for Therapeutic Intervention. Int J Mol Sci 2017; 18:ijms18010126. [PMID: 28075409 PMCID: PMC5297760 DOI: 10.3390/ijms18010126] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 12/16/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) Vpr protein is an attractive target for antiretroviral drug development. The conservation both of the structure along virus evolution and the amino acid sequence in viral isolates from patients underlines the importance of Vpr for the establishment and progression of HIV-1 disease. While its contribution to virus replication in dividing and non-dividing cells and to the pathogenesis of HIV-1 in many different cell types, both extracellular and intracellular forms, have been extensively studied, its precise mechanism of action nevertheless remains enigmatic. The present review discusses how the apparently multifaceted interplay between Vpr and host cells may be due to the impairment of basic metabolic pathways. Vpr protein modifies host cell energy metabolism, oxidative status, and proteasome function, all of which are likely conditioned by the concentration and multimerization of the protein. The characterization of Vpr domains along with new laboratory tools for the assessment of their function has become increasingly relevant in recent years. With these advances, it is conceivable that drug discovery efforts involving Vpr-targeted antiretrovirals will experience substantial growth in the coming years.
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Affiliation(s)
- María Eugenia González
- Unidad de Expresión Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Carretera de Majadahonda-Pozuelo Km 2, Majadahonda, 28220 Madrid, Spain.
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HIV Nef- and Notch1-dependent Endocytosis of ADAM17 Induces Vesicular TNF Secretion in Chronic HIV Infection. EBioMedicine 2016; 13:294-304. [PMID: 27773542 PMCID: PMC5264432 DOI: 10.1016/j.ebiom.2016.10.027] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/11/2016] [Accepted: 10/18/2016] [Indexed: 12/30/2022] Open
Abstract
Tumor necrosis factor (TNF) is a key cytokine in HIV replication and pathogenesis. For reasons that are not entirely clear, the cytokine remains upregulated despite anti-retroviral therapy (ART). Here we demonstrate that HIV Nef induces an alternative TNF secretion mechanism that remains active in chronic infection. Ingestion of Nef-containing plasma extracellular vesicles (pEV) from ART patients by primary immune cells, but also Nef expression, induced intracellular proTNF cleavage and secretion of vesicular TNF endosomes. Key event was the Nef-mediated routing of the TNF-converting enzyme ADAM17 into Rab4 + early endosomes and the Rab27 + secretory pathway. Analysis of lymph-node tissue by multi-epitope-ligand-cartography (MELC) confirmed a vesicular TNF secretion phenotype that co-localized with persistent Nef expression, and implicated Notch1 as an essential co-factor. Surprisingly Notch1 had no transcriptional effect but was required for the endosomal trafficking of ADAM17. We conclude that Nef expression and Nef-containing pEV mobilize TNF from endosomal compartments in acute and chronic infection. Nef/ADAM17 containing extracellular vesicles induce an endosomal TNF secretion type in primary target cells. The mechanism required the shuttling of ADAM17 into Rab4 + endosomal compartments in a Notch1-dependent manner. The mechanism could be demonstrated in tissue by multi-epitope-ligand-cartography (MELC) technology.
Despite antiviral therapy, plasma levels of TNF remain upregulated and likely play a role in many comorbidities seen in chronic HIV infection. We found that this is due to high levels of HIV-induced plasma extracellular vesicles (pEV) containing the TNF processing ADAM17 protease. Interestingly these vesicles induced a different TNF secretion type. Whereas TNF is usually shed from the plasma membrane, pEV mobilized intracellular TNF storage compartments, secreting endosomal vesicles. We could confirm this mechanism analyzing lymph node tissue sections by a novel immunostaining technology. Our report supports our previous publication implying ongoing viral activity despite successful antiretroviral therapy.
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HIV-1 Vpu Antagonizes CD317/Tetherin by Adaptor Protein-1-Mediated Exclusion from Virus Assembly Sites. J Virol 2016; 90:6709-6723. [PMID: 27170757 DOI: 10.1128/jvi.00504-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/06/2016] [Indexed: 01/22/2023] Open
Abstract
UNLABELLED The host cell restriction factor CD317/tetherin traps virions at the surface of producer cells to prevent their release. The HIV-1 accessory protein Vpu antagonizes this restriction. Vpu reduces the cell surface density of the restriction factor and targets it for degradation; however, these activities are dispensable for enhancing particle release. Instead, Vpu has been suggested to antagonize CD317/tetherin by preventing recycling of internalized CD317/tetherin to the cell surface, blocking anterograde transport of newly synthesized CD317/tetherin, and/or displacing the restriction factor from virus assembly sites at the plasma membrane. At the molecular level, antagonism relies on the physical interaction of Vpu with CD317/tetherin. Recent findings suggested that phosphorylation of a diserine motif enables Vpu to bind to adaptor protein 1 (AP-1) trafficking complexes via two independent interaction motifs and to couple CD317/tetherin to the endocytic machinery. Here, we used a panel of Vpu proteins with specific mutations in individual interaction motifs to define which interactions are required for antagonism of CD317/tetherin. Impairing recycling or anterograde transport of CD317/tetherin to the plasma membrane was insufficient for antagonism. In contrast, excluding CD317/tetherin from HIV-1 assembly sites depended on Vpu motifs for interaction with AP-1 and CD317/tetherin and correlated with antagonism of the particle release restriction. Consistently, interference with AP-1 function or its expression blocked these Vpu activities. Our results define displacement from HIV-1 assembly sites as active principle of CD317/tetherin antagonism by Vpu and support a role of tripartite complexes between Vpu, AP-1, and CD317/tetherin in this process. IMPORTANCE CD317/tetherin poses an intrinsic barrier to human immunodeficiency virus type 1 (HIV-1) replication in human cells by trapping virus particles at the surface of producer cells and thereby preventing their release. The viral protein Vpu antagonizes this restriction, and molecular interactions with the restriction factor and adaptor protein complex 1 (AP-1) were suggested to mediate this activity. Vpu modulates intracellular trafficking of CD317/tetherin and excludes the restriction factor from HIV-1 assembly sites at the plasma membrane, but the relative contribution of these effects to antagonism remain elusive. Using a panel of Vpu mutants, as well as interference with AP-1 function and expression, we show here that Vpu antagonizes CD317/tetherin by blocking its recruitment to viral assembly sites in an AP-1-dependent manner. These results refine our understanding of the molecular mechanisms of CD317/tetherin antagonism and suggest complexes of Vpu with the restriction factor and AP-1 as targets for potential therapeutic intervention.
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Kozma E, Nikić I, Varga BR, Aramburu IV, Kang JH, Fackler OT, Lemke EA, Kele P. Hydrophilic trans-Cyclooctenylated Noncanonical Amino Acids for Fast Intracellular Protein Labeling. Chembiochem 2016; 17:1518-24. [PMID: 27223658 DOI: 10.1002/cbic.201600284] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Indexed: 01/02/2023]
Abstract
Introduction of bioorthogonal functionalities (e.g., trans-cyclooctene-TCO) into a protein of interest by site-specific genetic encoding of non-canonical amino acids (ncAAs) creates uniquely targetable platforms for fluorescent labeling schemes in combination with tetrazine-functionalized dyes. However, fluorescent labeling of an intracellular protein is usually compromised by high background, arising from the hydrophobicity of ncAAs; this is typically compensated for by hours-long washout to remove excess ncAAs from the cellular interior. To overcome these problems, we designed, synthesized, and tested new, hydrophilic TCO-ncAAs. One derivative, DOTCO-lysine was genetically incorporated into proteins with good yield. The increased hydrophilicity shortened the excess ncAA washout time from hours to minutes, thus permitting rapid labeling and subsequent fluorescence microscopy.
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Affiliation(s)
- Eszter Kozma
- Hungarian Academy of Sciences, Research Centre for Natural Sciences, Institute of Organic Chemistry, Magyar tudósok krt. 2, 1117, Budapest, Hungary
| | - Ivana Nikić
- Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Balázs R Varga
- Hungarian Academy of Sciences, Research Centre for Natural Sciences, Institute of Organic Chemistry, Magyar tudósok krt. 2, 1117, Budapest, Hungary
| | - Iker Valle Aramburu
- Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Jun Hee Kang
- Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Oliver T Fackler
- Center of Infectious Diseases, Integrative Virology, University of Heidelberg, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
| | - Edward A Lemke
- Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany.
| | - Péter Kele
- Hungarian Academy of Sciences, Research Centre for Natural Sciences, Institute of Organic Chemistry, Magyar tudósok krt. 2, 1117, Budapest, Hungary.
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