1
|
Ramirez JM, Calderon-Zavala AC, Balaram A, Heldwein EE. In vitro reconstitution of herpes simplex virus 1 fusion identifies low pH as a fusion co-trigger. mBio 2023; 14:e0208723. [PMID: 37874146 PMCID: PMC10746285 DOI: 10.1128/mbio.02087-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 10/25/2023] Open
Abstract
Membrane fusion mediated by herpes simplex virus 1 (HSV-1) is a complex, multi-protein process that is receptor triggered and can occur both at the cell surface and in endosomes. To deconvolute this complexity, we reconstituted HSV-1 fusion with synthetic lipid vesicles in vitro. Using this simplified, controllable system, we discovered that HSV-1 fusion required not only a cognate host receptor but also low pH. On the target membrane side, efficient fusion required cholesterol, negatively charged lipids found in the endosomal membranes, and an optimal balance of lipid order and disorder. On the virion side, the four HSV-1 entry glycoproteins-gB, gD, gH, and gL-were sufficient for fusion. We propose that low pH is a biologically relevant co-trigger for HSV-1 fusion. The dependence of fusion on low pH and endosomal lipids could explain why HSV-1 enters most cell types by endocytosis. We hypothesize that under neutral pH conditions, other, yet undefined, cellular factors may serve as fusion co-triggers. The in vitro fusion system established here can be employed to systematically investigate HSV-1-mediated membrane fusion.IMPORTANCEHSV-1 causes lifelong, incurable infections and diseases ranging from mucocutaneous lesions to fatal encephalitis. Fusion of viral and host membranes is a critical step in HSV-1 infection of target cells that requires multiple factors on both the viral and host sides. Due to this complexity, many fundamental questions remain unanswered, such as the identity of the viral and host factors that are necessary and sufficient for HSV-1-mediated membrane fusion and the nature of the fusion trigger. Here, we developed a simplified in vitro fusion assay to examine the fusion requirements and identified low pH as a co-trigger for virus-mediated fusion in vitro. We hypothesize that low pH has a critical role in cell entry and, potentially, pathogenesis.
Collapse
Affiliation(s)
- J. Martin Ramirez
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Medical Scientist Training Program, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Ariana C. Calderon-Zavala
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Ariane Balaram
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Ekaterina E. Heldwein
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Medical Scientist Training Program, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| |
Collapse
|
2
|
Pietilä MK, Bachmann JJ, Ravantti J, Pelkmans L, Fraefel C. Cellular state landscape and herpes simplex virus type 1 infection progression are connected. Nat Commun 2023; 14:4515. [PMID: 37500668 PMCID: PMC10374626 DOI: 10.1038/s41467-023-40148-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 07/14/2023] [Indexed: 07/29/2023] Open
Abstract
Prediction, prevention and treatment of virus infections require understanding of cell-to-cell variability that leads to heterogenous disease outcomes, but the source of this heterogeneity has yet to be clarified. To study the multimodal response of single human cells to herpes simplex virus type 1 (HSV-1) infection, we mapped high-dimensional viral and cellular state spaces throughout the infection using multiplexed imaging and quantitative single-cell measurements of viral and cellular mRNAs and proteins. Here we show that the high-dimensional cellular state scape can predict heterogenous infections, and cells move through the cellular state landscape according to infection progression. Spatial information reveals that infection changes the cellular state of both infected cells and of their neighbors. The multiplexed imaging of HSV-1-induced cellular modifications links infection progression to changes in signaling responses, transcriptional activity, and processing bodies. Our data show that multiplexed quantification of responses at the single-cell level, across thousands of cells helps predict infections and identify new targets for antivirals.
Collapse
Affiliation(s)
- Maija K Pietilä
- Institute of Virology, University of Zurich, Zurich, Switzerland.
| | - Jana J Bachmann
- Institute of Virology, University of Zurich, Zurich, Switzerland
| | - Janne Ravantti
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Lucas Pelkmans
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Cornel Fraefel
- Institute of Virology, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
3
|
Ethosomal Gel for Topical Administration of Dimethyl Fumarate in the Treatment of HSV-1 Infections. Int J Mol Sci 2023; 24:ijms24044133. [PMID: 36835541 PMCID: PMC9967198 DOI: 10.3390/ijms24044133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
The infections caused by the HSV-1 virus induce lesions on the lips, mouth, face, and eye. In this study, an ethosome gel loaded with dimethyl fumarate was investigated as a possible approach to treat HSV-1 infections. A formulative study was conducted, evaluating the effect of drug concentration on size distribution and dimensional stability of ethosomes by photon correlation spectroscopy. Ethosome morphology was investigated by cryogenic transmission electron microscopy, while the interaction between dimethyl fumarate and vesicles, and the drug entrapment capacity were respectively evaluated by FTIR and HPLC. To favor the topical application of ethosomes on mucosa and skin, different semisolid forms, based on xanthan gum or poloxamer 407, were designed and compared for spreadability and leakage. Dimethyl fumarate release and diffusion kinetics were evaluated in vitro by Franz cells. The antiviral activity against HSV-1 was tested by plaque reduction assay in Vero and HRPE monolayer cells, while skin irritation effect was evaluated by patch test on 20 healthy volunteers. The lower drug concentration was selected, resulting in smaller and longer stable vesicles, mainly characterized by a multilamellar organization. Dimethyl fumarate entrapment in ethosome was 91% w/w, suggesting an almost total recovery of the drug in the lipid phase. Xanthan gum 0.5%, selected to thicken the ethosome dispersion, allowed to control drug release and diffusion. The antiviral effect of dimethyl fumarate loaded in ethosome gel was demonstrated by a reduction in viral growth both 1 h and 4 h post-infection. Moreover, the patch test demonstrated the safety of the ethosomal gel applied on the skin.
Collapse
|
4
|
Sicurella M, Sguizzato M, Cortesi R, Huang N, Simelière F, Montesi L, Marconi P, Esposito E. Mangiferin-Loaded Smart Gels for HSV-1 Treatment. Pharmaceutics 2021; 13:pharmaceutics13091323. [PMID: 34575399 PMCID: PMC8465222 DOI: 10.3390/pharmaceutics13091323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/10/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
Infections due to HSV-1 affect many people all over the world. To counteract this pathology, usually characterized by perioral sores or by less frequent serious symptoms including keratitis, synthetic antiviral drugs are employed, such as acyclovir, often resulting in resistant viral strains under long-term use. Many plant-derived compounds, such as mangiferin and quercetin, have demonstrated antiviral potentials. In this study, smart semisolid forms based on phosphatidylcholine and Pluronic were investigated as delivery systems to administer mangiferin on skin and mucosae affected by HSV-1 infection. Particularly, lecithin organogels, Pluronic gel, and Pluronic lecithin organogels were formulated and characterized. After the selection of gel compositions, physical aspects, such as rheological behavior, spreadability, leakage, and adhesion were evaluated, suggesting a scarce suitability of the lecithin organogel for topical administration. Mangiferin was efficiently included in all type of gels. An in vitro study based on the Franz cell enabled us to find evidence of the gel capability to control drug diffusion, especially in the case of Pluronic organogel, while an in vivo study conducted on human volunteers demonstrated the safeness of all of the gels after cutaneous administration. Furthermore, a plaque reduction assay demonstrated the virucidal effect of mangiferin loaded in a Pluronic gel and a Pluronic lecithin organogel against the HSV-1 KOS strain.
Collapse
Affiliation(s)
- Mariaconcetta Sicurella
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, I-44121 Ferrara, Italy; (M.S.); (M.S.); (R.C.)
| | - Maddalena Sguizzato
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, I-44121 Ferrara, Italy; (M.S.); (M.S.); (R.C.)
| | - Rita Cortesi
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, I-44121 Ferrara, Italy; (M.S.); (M.S.); (R.C.)
| | - Nicolas Huang
- CNRS, Institut Galien Paris-Saclay, Université Paris-Saclay, 92296 Châtenay-Malabry, France; (N.H.); (F.S.)
| | - Fanny Simelière
- CNRS, Institut Galien Paris-Saclay, Université Paris-Saclay, 92296 Châtenay-Malabry, France; (N.H.); (F.S.)
| | - Leda Montesi
- Cosmetology Center, University of Ferrara, I-44121 Ferrara, Italy;
| | - Peggy Marconi
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, I-44121 Ferrara, Italy; (M.S.); (M.S.); (R.C.)
- Correspondence: (P.M.); (E.E.)
| | - Elisabetta Esposito
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, I-44121 Ferrara, Italy; (M.S.); (M.S.); (R.C.)
- Correspondence: (P.M.); (E.E.)
| |
Collapse
|
5
|
Meier AF, Tobler K, Michaelsen K, Vogt B, Henckaerts E, Fraefel C. Herpes Simplex Virus 1 Coinfection Modifies Adeno-associated Virus Genome End Recombination. J Virol 2021; 95:e0048621. [PMID: 33853961 PMCID: PMC8315985 DOI: 10.1128/jvi.00486-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 04/05/2021] [Indexed: 11/20/2022] Open
Abstract
Wild-type adeno-associated virus (AAV) can only replicate in the presence of helper factors, which can be provided by coinfecting helper viruses such as adenoviruses and herpesviruses. The AAV genome consists of a linear, single-stranded DNA (ssDNA), which is converted into different molecular structures within the host cell. Using high-throughput sequencing, we found that herpes simplex virus 1 (HSV-1) coinfection leads to a shift in the type of AAV genome end recombination. In particular, open-end inverted terminal repeat (ITR) recombination was enhanced, whereas open-closed ITR recombination was reduced in the presence of HSV-1. We demonstrate that the HSV-1 protein ICP8 plays an essential role in HSV-1-mediated interference with AAV genome end recombination, indicating that the previously described ICP8-driven mechanism of HSV-1 genome recombination may be underlying the observed changes. We also provide evidence that additional factors, such as products of true late genes, are involved. Although HSV-1 coinfection significantly changed the type of AAV genome end recombination, no significant change in the amount of circular AAV genomes was identified. IMPORTANCE Adeno-associated virus (AAV)-mediated gene therapy represents one of the most promising approaches for the treatment of genetic diseases. Currently, various GMP-compatible production methods can be applied to manufacture clinical-grade vector, including methods that employ helper factors derived from herpes simplex virus 1 (HSV-1). Yet, to date, we do not fully understand how HSV-1 interacts with AAV. We observed that HSV-1 modulates AAV genome ends similarly to the genome recombination events observed during HSV-1 replication and postulate that further improvements of the HSV-1 production platform may enhance packaging of the recombinant AAV particles.
Collapse
Affiliation(s)
| | - Kurt Tobler
- Institute of Virology, University of Zürich, Zurich, Switzerland
| | - Kevin Michaelsen
- Institute of Virology, University of Zürich, Zurich, Switzerland
| | - Bernd Vogt
- Institute of Virology, University of Zürich, Zurich, Switzerland
| | - Els Henckaerts
- Laboratory of Viral Cell Biology & Therapeutics, Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King’s College London, London, United Kingdom
| | - Cornel Fraefel
- Institute of Virology, University of Zürich, Zurich, Switzerland
| |
Collapse
|
6
|
Meier AF, Tobler K, Leisi R, Lkharrazi A, Ros C, Fraefel C. Herpes simplex virus co-infection facilitates rolling circle replication of the adeno-associated virus genome. PLoS Pathog 2021; 17:e1009638. [PMID: 34061891 PMCID: PMC8195378 DOI: 10.1371/journal.ppat.1009638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/11/2021] [Accepted: 05/13/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated virus (AAV) genome replication only occurs in the presence of a co-infecting helper virus such as adenovirus type 5 (AdV5) or herpes simplex virus type 1 (HSV-1). AdV5-supported replication of the AAV genome has been described to occur in a strand-displacement rolling hairpin replication (RHR) mechanism initiated at the AAV 3' inverted terminal repeat (ITR) end. It has been assumed that the same mechanism applies to HSV-1-supported AAV genome replication. Using Southern analysis and nanopore sequencing as a novel, high-throughput approach to study viral genome replication we demonstrate the formation of double-stranded head-to-tail concatemers of AAV genomes in the presence of HSV-1, thus providing evidence for an unequivocal rolling circle replication (RCR) mechanism. This stands in contrast to the textbook model of AAV genome replication when HSV-1 is the helper virus.
Collapse
Affiliation(s)
| | - Kurt Tobler
- Institute of Virology, University of Zurich, Zurich, Switzerland
| | - Remo Leisi
- Department for Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Anouk Lkharrazi
- Institute of Virology, University of Zurich, Zurich, Switzerland
| | - Carlos Ros
- Department for Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Cornel Fraefel
- Institute of Virology, University of Zurich, Zurich, Switzerland
| |
Collapse
|