Unravelling cell entry pathway of Equine Arteritis Virus entry by an antisense RNA approach

ABSTRACT Alpha interferon (IFN-α) induces the transfer of resistance to hepatitis B virus (HBV) from liver nonparenchymal cells (LNPCs) to hepatocytes via exosomes. However, little is known about the entry machinery and pathway involved in the transmission of IFN-α-induced antiviral activity. In this study, we found that macrophage exosomes uniquely depend on T cell immunoglobulin and mucin receptor 1 (TIM-1), a hepatitis A virus (HAV) receptor, to enter hepatocytes for delivering IFN-α-induced anti-HBV activity. Moreover, two primary endocytic routes for virus infection, clathrin-mediated endocytosis (CME) and macropinocytosis, collaborate to permit exosome entry and anti-HBV activity transfer. Subsequently, lysobisphosphatidic acid (LBPA), an anionic lipid closely related to endosome penetration of virus, facilitates membrane fusion of exosomes in late endosomes/multivesicular bodies (LEs/MVBs) and the accompanying exosomal cargo uncoating. Together, our findings provide comprehensive insights into the transmission route of macrophage exosomes to efficiently deliver IFN-α-induced antiviral substances and highlight the similarities between the entry mechanisms of exosomes and virus.IMPORTANCE Our previous study showed that LNPC-derived exosomes could transmit IFN-α-induced antiviral activity to HBV replicating hepatocytes, but the concrete transmission mechanisms, which include exosome entry and exosomal cargo release, remain unclear. In this study, we found that virus entry machinery and pathway were also applied to exosome-mediated cell-to-cell antiviral activity transfer. Macrophage-derived exosomes distinctively exploit hepatitis A virus receptor for access to hepatocytes. Later, CME and macropinocytosis are utilized by exosomes, followed by exosome-endosome fusion for efficient transfer of IFN-α-induced anti-HBV activity. We believe that understanding the cellular entry pathway of exosomes will be beneficial to designing exosomes as efficient vehicles for antiviral therapy.

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Equine Arteritis Virus Uses Equine CXCL16 as an Entry Receptor

Journal of Virology ◽

10.1128/jvi.02455-15 ◽

2016 ◽

Vol 90 (7) ◽

pp. 3366-3384 ◽

Cited By ~ 14

Author(s):

Sanjay Sarkar ◽

Lakshman Chelvarajan ◽

Yun Young Go ◽

Frank Cook ◽

Sergey Artiushin ◽

...

Keyword(s):

Transmembrane Protein ◽

Critical Role ◽

Equine Arteritis Virus ◽

Cell Entry ◽

Significant Advance ◽

Type I ◽

Small Interfering Rnas ◽

Chromosome 11 ◽

Trade Restrictions ◽

Entry Receptor

ABSTRACTPrevious studies in our laboratory have identified equine CXCL16 (EqCXCL16) to be a candidate molecule and possible cell entry receptor for equine arteritis virus (EAV). In horses, the CXCL16 gene is located on equine chromosome 11 (ECA11) and encodes a glycosylated, type I transmembrane protein with 247 amino acids. Stable transfection of HEK-293T cells with plasmid DNA carrying EqCXCL16 (HEK-EqCXCL16 cells) increased the proportion of the cell population permissive to EAV infection from <3% to almost 100%. The increase in permissiveness was blocked either by transfection of HEK-EqCXCL16 cells with small interfering RNAs (siRNAs) directed against EqCXCL16 or by pretreatment with guinea pig polyclonal antibody against EqCXCL16 protein (Gp anti-EqCXCL16 pAb). Furthermore, using a virus overlay protein-binding assay (VOPBA) in combination with far-Western blotting, gradient-purified EAV particles were shown to bind directly to the EqCXCL16 proteinin vitro. The binding of biotinylated virulent EAV strain Bucyrus at 4°C was significantly higher in HEK-EqCXCL16 cells than nontransfected HEK-293T cells. Finally, the results demonstrated that EAV preferentially infects subpopulations of horse CD14+monocytes expressing EqCXCL16 and that infection of these cells is significantly reduced by pretreatment with Gp anti-EqCXCL16 pAb. The collective data from this study provide confirmatory evidence that the transmembrane form of EqCXCL16 likely plays a major role in EAV host cell entry processes, possibly acting as a primary receptor molecule for this virus.IMPORTANCEOutbreaks of EVA can be a source of significant economic loss for the equine industry from high rates of abortion in pregnant mares, death in young foals, establishment of the carrier state in stallions, and trade restrictions imposed by various countries. Similar to other arteriviruses, EAV primarily targets cells of the monocyte/macrophage lineage, which, when infected, are believed to play a critical role in EVA pathogenesis. To this point, however, the host-specified molecules involved in EAV binding and entry into monocytes/macrophages have not been identified. Identification of the cellular receptors for EAV may provide insights to design antivirals and better prophylactic reagents. In this study, we have demonstrated that EqCXCL16 acts as an EAV entry receptor in EAV-susceptible cells, equine monocytes. These findings represent a significant advance in our understanding of the fundamental mechanisms associated with the entry of EAV into susceptible cells.

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Evaluation of Flavonoids as 2019-nCoV Cell Entry Inhibitor Through Molecular Docking and Pharmacological Analysis

10.26434/chemrxiv.12071508 ◽

2020 ◽

Cited By ~ 2

Author(s):

Deep Bhowmik ◽

Rajat Nandi ◽

Diwakar Kumar

Keyword(s):

Molecular Docking ◽

Host Cell ◽

Drug Targets ◽

Virus Entry ◽

Cell Entry ◽

Entry Inhibitor ◽

Minimal Toxicity ◽

Pharmacological Analysis ◽

Rapid Spread ◽

Effective Drugs

In this study we aimed at the receipt binding domain of S protein and ACE-2 receptor as a promising drug targets against SARS-CoV-2. Flavonoids with anti-viral properties were taken as ligand for molecular docking. Selected flavonoids showed extremely good pharmacokinetics properties with good absorption, solubility, metabolism, excretion,distribution, bioavailability and minimal toxicity. These identified lead flavonoids may act as potential compound for the development of effective drugs and may help in controlling the rapid spread of SARS-CoV-2 by potentially inhibiting the virus entry into the host cell.

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Heparan sulfate assists SARS-CoV-2 in cell entry and can be targeted by approved drugs in vitro

Cell Discovery ◽

10.1038/s41421-020-00222-5 ◽

2020 ◽

Vol 6 (1) ◽

Cited By ~ 3

Author(s):

Qi Zhang ◽

Catherine Zhengzheng Chen ◽

Manju Swaroop ◽

Miao Xu ◽

Lihui Wang ◽

...

Keyword(s):

Cell Surface ◽

Heparan Sulfate ◽

Viral Entry ◽

Drug Repurposing ◽

Cell Entry ◽

Entry Pathway ◽

Viral Particles ◽

Approved Drugs ◽

Attachment Factor

Abstract The cell entry of SARS-CoV-2 has emerged as an attractive drug repurposing target for COVID-19. Here we combine genetics and chemical perturbation to demonstrate that ACE2-mediated entry of SARS-Cov and CoV-2 requires the cell surface heparan sulfate (HS) as an assisting cofactor: ablation of genes involved in HS biosynthesis or incubating cells with a HS mimetic both inhibit Spike-mediated viral entry. We show that heparin/HS binds to Spike directly, and facilitates the attachment of Spike-bearing viral particles to the cell surface to promote viral entry. We screened approved drugs and identified two classes of inhibitors that act via distinct mechanisms to target this entry pathway. Among the drugs characterized, Mitoxantrone is a potent HS inhibitor, while Sunitinib and BNTX disrupt the actin network to indirectly abrogate HS-assisted viral entry. We further show that drugs of the two classes can be combined to generate a synergized activity against SARS-CoV-2-induced cytopathic effect. Altogether, our study establishes HS as an attachment factor that assists SARS coronavirus cell entry and reveals drugs capable of targeting this important step in the viral life cycle.

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Adenovirus Entry: From Infection to Immunity

Annual Review of Virology ◽

10.1146/annurev-virology-092818-015550 ◽

2019 ◽

Vol 6 (1) ◽

pp. 177-197 ◽

Cited By ~ 26

Author(s):

Urs F. Greber ◽

Justin W. Flatt

Keyword(s):

Epithelial Cells ◽

Deep Understanding ◽

Cell Entry ◽

Cellular Biology ◽

Entry Pathway ◽

Risk Of Death ◽

Specific Host ◽

Physical Virology ◽

Antigen Presenting ◽

And Control

More than 80 different adenovirus (AdV) types infect humans through the respiratory, ocular, or gastrointestinal tracts. They cause acute clinical mani-festations or persist under humoral and cell-based immunity. Immuno-suppressed individuals are at risk of death from an AdV infection. Concepts about cell entry of AdV build on strong foundations from molecular and cellular biology—and increasingly physical virology. Here, we discuss how virions enter and deliver their genome into the nucleus of epithelial cells. This process breaks open the virion at distinct sites because the particle has nonisometric mechanical strength and reacts to specific host factors along the entry pathway. We further describe how macrophages and dendritic cells resist AdV infection yet enhance productive entry into polarized epithelial cells. A deep understanding of the viral mechanisms and cell biological and biophysical principles will continue to unravel how epithelial and antigen-presenting cells respond to AdVs and control inflammation and persistence in pathology and therapy.

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Hepatitis E Virus Entry

Viruses ◽

10.3390/v11100883 ◽

2019 ◽

Vol 11 (10) ◽

pp. 883 ◽

Cited By ~ 6

Author(s):

Yin ◽

Feng

Keyword(s):

Acute Hepatitis ◽

Hepatitis E Virus ◽

Virus Entry ◽

Hepatitis E ◽

Cell Entry ◽

Current Understanding ◽

Virus Spread ◽

Entry Mechanism ◽

The Way

Hepatitis E virus (HEV) infection is a major cause of acute hepatitis worldwide. It is transmitted enterically but replicates in the liver. Recent studies indicate that HEV exists in two forms: naked, nonenveloped virions that are shed into feces to mediate inter-host transmission, and membrane-cloaked, quasienveloped virions that circulate in the bloodstream to mediate virus spread within a host. Both virion types are infectious, but differ in the way they infect cells. Elucidating the entry mechanism for both virion types is essential to understand HEV biology and pathogenesis, and is relevant to the development of treatments and preventions for HEV. This review summarizes the current understanding of the cell entry mechanism for these two HEV virion types.

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Faculty Opinions recommendation of Dissecting the cell entry pathway of dengue virus by single-particle tracking in living cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1147345.604504 ◽

2009 ◽

Author(s):

Adolfo Garcia-Sastre ◽

Donna M Tscherne

Keyword(s):

Dengue Virus ◽

Particle Tracking ◽

Single Particle ◽

Living Cells ◽

Single Particle Tracking ◽

Cell Entry ◽

Entry Pathway

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Morphological Changes in the T=3 Capsid of Flock House Virus during Cell Entry

Journal of Virology ◽

10.1128/jvi.80.2.615-622.2006 ◽

2006 ◽

Vol 80 (2) ◽

pp. 615-622 ◽

Cited By ~ 14

Author(s):

Hanna E. Walukiewicz ◽

John E. Johnson ◽

Anette Schneemann

Keyword(s):

Morphological Changes ◽

Cell Entry ◽

Flock House Virus ◽

Morphological Alterations ◽

Entry Pathway ◽

Defective Mutant ◽

The Family ◽

Initial Binding ◽

Identification And Characterization

ABSTRACT We report the identification and characterization of a viral intermediate formed during infection of Drosophila cells with the nodavirus Flock House virus (FHV). We observed that even at a very low multiplicity of infection, only 70% of the input virus stayed attached to or entered the cells, while the remaining 30% of the virus eluted from cells after initial binding. The eluted FHV particles did not rebind to Drosophila cells and, thus, could no longer initiate infection by the receptor-mediated entry pathway. FHV virus-like particles with the same capsid composition as native FHV but containing cellular RNA also exhibited formation of eluted particles when incubated with the cells. A maturation cleavage-defective mutant of FHV, however, did not. Compared to naïve FHV particles, i.e., particles that had never been incubated with cells, eluted particles showed an acid-sensitive phenotype and morphological alterations. Furthermore, eluted particles had lost a fraction of the internally located capsid protein gamma. Based on these results, we hypothesize that FHV eluted particles represent an infection intermediate analogous to eluted particles observed for members of the family Picornaviridae.

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Activation of a Cell Entry Pathway Common to Type C Mammalian Retroviruses by Soluble Envelope Fragments

Journal of Virology ◽

10.1128/jvi.74.1.295-304.2000 ◽

2000 ◽

Vol 74 (1) ◽

pp. 295-304 ◽

Cited By ~ 66

Author(s):

Dimitri Lavillette ◽

Alessia Ruggieri ◽

Stephen J. Russell ◽

François-Loïc Cosset

Keyword(s):

Specific Interaction ◽

Cell Entry ◽

Target Cells ◽

Amino Terminal ◽

Entry Pathway ◽

Defective Mutant ◽

Fusion Defect ◽

A Cell ◽

Type C ◽

Leukemia Viruses

ABSTRACT Mutations that negatively or positively affect the fusion properties of murine leukemia viruses (MLVs) have been found within all subdomains of their SU (surface) and TM (transmembrane) envelope units. Yet, the interrelations between these different regions of the envelope complex during the cell entry process are still elusive. Deletion of the histidine residue of the conserved PHQV motif at the amino terminus of the amphotropic or the ecotropic MLV SU resulted in the AdelH or the MOdelH fusion-defective mutant envelope, respectively. These delH mutant envelopes are incorporated on retroviral particles at normal densities and normally mediate virion binding to cells expressing the retroviral receptors. However, both their cell-cell and virus-cell fusogenicities were fully prevented at an early postbinding stage. We show here that the fusion defect of AdelH or MOdelH envelopes was also almost completely reverted by providing either soluble SU or a polypeptide encompassing the receptor-binding domain (RBD) to the target cells, provided that the integrity of the amino-terminal end of either polypeptide was preserved. Restoration of delH envelope fusogenicity was caused by activation of the target cells via specific interaction of the latter polypeptides with the retrovirus receptor rather than by their association with the delH envelope complexes. Moreover crossactivation of the target cells, leading to fusion activation of AdelH or MOdelH envelopes, was achieved by polypeptides containing various type C mammalian retrovirus RBDs, irrespective of the type of entry-defective glycoprotein that was used for infection. Our results indicate that although they recognize different receptors for binding to the cell surface, type C mammalian retroviruses use a common entry pathway which is activated by a conserved feature of their envelope glycoproteins.

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