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Antiviral Activity of Plantago asiatica Polysaccharide against Pseudorabies Virus In Vitro.

Pseudorabies (PR) is an acute infectious disease of various domestic animals and wild animals caused by pseudorabies virus (PRV). It is mainly characterized by fever, itching, encephalomyelitis, and respiratory and neurological disorders. Plantago asiatica polysaccharide (PLP), extracted from the whole plant of Plantago asiatica L., showed immunomodulatory and antioxidation effects, but the antiviral activity had not been reported. In this study, the inhibitory effect of PLP on PRV infection was studied. Our study first revealed that PLP could inhibit PRV infection in a dose-dependent manner.

A sensor-adaptor mechanism for enterovirus uncoating from structures of EV71.

Enterovirus 71 (EV71) is a major agent of hand, foot and mouth disease in children that can cause severe central nervous system disease and death. No vaccine or antiviral therapy is available. High-resolution structural analysis of the mature virus and natural empty particles shows that the mature virus is structurally similar to other enteroviruses. In contrast, the empty particles are markedly expanded and resemble elusive enterovirus-uncoating intermediates not previously characterized in atomic detail. Hydrophobic pockets in the EV71 capsid are collapsed in this expanded particle, providin

Sequence analysis of the small RNA segment of guinea pig-passaged Pichinde virus variants.

The established animal model for Lassa fever is based on the new world arenavirus Pichinde (PIC). Natural isolates of PIC virus are attenuat … is conceivable that mutations at this site could influence virulence by altering B cell epitopes or virus attachment protein conformation.

[Host-adaptive mechanism of H5N1 avian influenza virus hemagglutininn].

The H5N1 subtype is a highly pathogenic avian influenza virus currently circulating in birds in parts of Asia and northeast Africa, which has caused fatal human infections since 1997. Continuous circulation of the virus in endemic areas has allowed genetically diverse viruses to emerge, increasing the risk of H5N1 human infection. Although human infections with H5N1 have to date been limited, experimental evidence of the aerosol transmission of mutated viruses in a mammalian infection model has revealed the pandemic potential of H5N1 virus. One of the most important viral factors for host-adap

Envelope proteins as antiviral drug target.

Attachment of a virus with a specific receptor on the cell surface is the first and foremost step in virus infection. In case of enveloped viruses, their interaction with the host cell receptor is mediated by viral encoded glycoproteins on its envelope, a host derived lipid bilayer. Since, virus entry is a multistep process, after receptor recognition, envelope proteins mediate internalisation of virus particles into the host cell. Envelope glycoproteins are the first proteins that the host immune system encounters upon infection. Thus, envelope proteins are important drug target with multiple

Синтетические полимерные ингибиторы ингибиторов вируса гриппа, имеющие обязательную силу.

Anomeric aminobenzilglycosides Neu5Ac были объединены с полиакрилатом, а ряд полученных синтетических поливалентных сиалозондов были исследованы в качестве ингибиторов связи с вирусом гриппа. Ингибиционная активность полимерных силиазонов в значительной степени зависит от содержания остатков Neu5Ac и характера перевозчика. Полиакриловый полимер, содержащий 10 моль Neu5Ac, на 3 порядка более мощный ингибитор, чем соответствующий моновалент бензилсиалозад, и значительно более активный, чем фетуин.

Совпадение в аннотации оригинала
Anomeric aminobenzylglycosides of Neu5Ac were coupled with the polyacrylate carrier and a number of synthetic polyvalent sialosides obtained were investigated as inhibitors of influenza virus attachment. The inhibitory activity of polymeric sialosides is highly dependent upon the Neu5Ac residue content and the nature of the carrier. The polyacrylic acid base…

Revealing In Silico that Bacteria's Outer Membrane Proteins may Help our Bodies Replicate and Carry Severe Acute Respiratory Syndrome Coronavirus 2.

Some studies in the literature show that viruses can affect bacteria directly or indirectly, and viruses use their own specific ways to do these interactions. Furthermore, it is said that bacteria are prone to attachment mammalian cells during a viral illness using their surface proteins that bind to host extracellular matrix proteins such as fibronectin, fibrinogen, vitronectin, and elastin. A recent study identified the cooperation between bacteria and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in silico, in vitro, and in vivo. Like this study, we hypothesized that more bac

Lymphocytic choriomeningitis virus. X. Demonstration of nucleoprotein on the surface of infected cells.

Of a total of 17 monoclonal antibodies (MAb) directed against structural proteins of the lymphocytic choriomeningitis (LCM) virus, 3 were specific for the viral nucleoprotein (p63) and attached to the plasma membrane of infected cells, as disclosed by the indirect immunofluorescence procedure and complement-mediated cytolysis. We had previously demonstrated that a portion of the nucleoprotein (p63E) was part of the envelope of the intact virion (M. Bruns, W. Zeller, H. Rohdewohld, and F. Lehmann-Grube (1986) Virology 151, 77-85), and we now show that after external iodination of virions follow

DC-SIGN and L-SIGN Are Attachment Factors That Promote Infection of Target Cells by Human Metapneumovirus in the Presence or Absence of Cellular Glycosaminoglycans.

UNLABELLED: It is well established that glycosaminoglycans (GAGs) function as attachment factors for human metapneumovirus (HMPV), concentrating virions at the cell surface to promote interaction with other receptors for virus entry and infection. There is increasing evidence to suggest that multiple receptors may exhibit the capacity to promote infectious entry of HMPV into host cells; however, definitive identification of specific transmembrane receptors for HMPV attachment and entry is complicated by the widespread expression of cell surface GAGs. pgsA745 Chinese hamster ovary (CHO) cells a

Deglycosylation of hepatitis C virus pseudoparticles with 2-3,6,8,9 Neuraminidase A elicits protective neutralizing antibodies in mice.

Hepatitis C virus continues to be a major global health burden, infecting 58 million people and claiming 300,000 lives yearly. At present, no vaccine exists to prevent this disease. Viral attachment and entry are major targets of adaptive humoral responses. However, viral proteins responsible for cell attachment and entry of HCV are the glycoproteins E1 and E2, which are highly glycosylated, leading to the evasion of HCV from the humoral immune response. In this study, HCV pseudoparticles (HCVpp) were produced by transfecting 293T cells with three vectors required to assemble infectious pseudo

Enterovirus 70 binds to different glycoconjugates containing alpha2,3-linked sialic acid on different cell lines.

Enterovirus 70 (EV70), the causative agent of acute hemorrhagic conjunctivitis, exhibits a restricted tropism for conjunctival and corneal c … t EV70 recognizes alpha2,3-linked sialic acid on human corneal epithelial cells and on U-937 cells. Virus attachment to both cell lines is CD55 independent and sensitive to benzyl N-acetyl-alpha-D-galactosaminide, an inhibitor of O-linked glycosylation. Virus binding to corneal cells, but not U-937 cells, is inhibited by proteinase K, but not by phosphatidylinosit …

Random sequential adsorption of human adenovirus 2 onto polyvinylidene fluoride surface influenced by extracellular polymeric substances.

Virus removal by membrane bioreactors depends on virus-membrane and virus-foulant interactions. The adsorption of human adenovirus 2 (HAdV-2) on polyvinylidene fluoride (PVDF) membrane and a major membrane foulant, extracellular polymeric substances (EPS), were measured in a quartz crystal microbalance. In 3-100mM CaCl2 solutions, irreversible adsorption of HAdV-2 was observed on both pristine and EPS-fouled PVDF surfaces. The HAdV-2 adsorption kinetics was successfully fitted with the random sequential adsorption (RSA) model. The applicability of the RSA model for HAdV-2 adsorption is confirm

Antiviral effect of the heparan sulfate mimetic, PI-88, against dengue and encephalitic flaviviruses.

Many viruses, including flaviviruses, display affinity for cell surface heparan sulfate (HS) proteoglycans with biological relevance in virus attachment/entry. This raises the possibility of the application of HS mimetics in antiviral therapy. We have evaluated the antiviral effect of the sulfated polysaccharides, suramin, pentosan polysulfate (PPS) and PI-88, which are currently approved or in trial for clinical use, against dengue virus (DEN) and the encephalitic flaviviruses, Japanese encephalitis virus, West Nile virus, and Murray Valley encephalitis virus. A flow cytometry-based method fo…

Sequence heterogeneity in pneumonia virus of mice reveals G gene-dependent modulation of virulence.

UNLABELLED: Pneumonia virus of mice (PVM), the mouse homolog to respiratory syncytial virus (RSV), is increasingly used as a surrogate model to study pneumovirus pathogenesis in a more natural pathogen-host relationship. Two major strains of PVM, strain 15 and J3666, are currently used in laboratories, with preferences for either one or the other based on the well-documented isolation history of strain 15, or the suggested higher virulence of strain J3666. Using conventional and long-read sequencing, we found that the PVM strain J3666 represents two distinct virus populations, which are define

Inhibition of poxvirus maturation by rifamycin derivatives and related compounds.

The effect of a number of rifamycin derivatives and related compounds on the reversibility of the rifampin-induced virus maturation block was studied by using BHK-21 cells infected with vaccinia virus. All of the derivatives of 3-formyl rifamycin SV maintained this block, the required concentration varying from 100 to 1,000 mug/ml. These compounds vary only in the nature of the side-chain attached to the 3C atom on the naphthohydroquinone moiety; no obvious correlation between the nature of this side-chain and antiviral activity was found. Streptovaricin complex and tolypomycin R also maintain

Roles of the Chemokine Receptor CX3CR1 in the Pathogenesis of RSV Infections.

CX3CR1 is a chemokine receptor expressed on respiratory epithelial and immune cells and has been identified as a host factor important for infections with respiratory syncytial virus (RSV). In this review, we discuss the roles CX3CR1 plays in the pathogenesis of RSV infections as a viral entry receptor and regulator of immune cell trafficking. The conserved CX3C motif of the RSV G glycoprotein binds to CX3CR1 to mediate viral attachment and entry into respiratory epithelial cells. Furthermore, soluble G protein (sG) can bind to CX3CR1 and competitively interfere with cell signaling induced by

MDCK-B4GalNT2 cells disclose a α2,3-sialic acid requirement for the 2009 pandemic H1N1 A/California/04/2009 and NA aid entry of A/WSN/33.

Switching of receptor binding preference has been widely considered as one of the necessary mutations for avian influenza viruses, enabling efficient transmissions between human hosts. By stably overexpressing B4GalNT2 gene in MDCK cells, surface α2,3-siallylactose receptors were modified without affecting α2,6-receptor expression. The cell line MDCK-B4GalNT2 was used as a tool to screen for α2,3-receptor requirements in a panel of influenza viruses with previously characterized glycan array data. Infection of viruses with α2,3-receptor binding capability was inhibited in MDCK-B4GalNT2 cells,

1918 Influenza receptor binding domain variants bind and replicate in primary human airway cells regardless of receptor specificity.

The 1918 influenza pandemic caused ~50 million deaths. Many questions remain regarding the origin, pathogenicity, and mechanisms of human adaptation of this virus. Avian-adapted influenza A viruses preferentially bind α2,3-linked sialic acids (Sia) while human-adapted viruses preferentially bind α2,6-linked Sia. A change in Sia preference from α2,3 to α2,6 is thought to be a requirement for human adaptation of avian influenza viruses. Autopsy data from 1918 cases, however, suggest that factors other than Sia preference played a role in viral binding and entry to human airway cells. Here, we ev

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may be harmful in patients with diabetes during COVID-19 pandemic.

The novel coronavirus disease 2019 (COVID-19) outbreak once again demonstrated the importance of the renin-angiotensin system (RAS) in patients with diabetes. Activation of the RAS increases in patients with diabetes. The virus attaches to the ACE2 enzyme at low cytosolic pH values and enters into the cell and causes infection. Especially in the presence of diabetes mellitus and accompanying comorbid conditions such as hypertension, obesity, old age, and smoking, cytosolic pH is low, thus the virus easily may enter the cell by attaching to ACE2. ACEIs and ARBs lead to a reduction in angiotensi

Highly pathogenic avian influenza virus H7N7 isolated from a fatal human case causes respiratory disease in cats but does not spread systemically.

Highly pathogenic avian influenza viruses (HPAIV) of the H5 and H7 subtypes primarily infect poultry but are occasionally transmitted to humans and other mammalian species, often causing severe disease. Previously we have shown that HPAIV H5N1 causes severe systemic disease in cats. In this study, we investigated whether HPAIV H7N7 isolated from a fatal human case is also able to cause disease in cats. Additionally, we compared the cell tropism of both viruses by immunohistochemistry and virus histochemistry. Three domestic cats were inoculated intratracheally with HPAIV H7N7. Virus excretion