564. A Cationic Peptide Encoded by Influenza Virus A (H5N1) Can Operate as a Protein Carrier In Vitro and In Vivo

Baicalin (BA) is a flavonoid compound purified fromScutellaria baicalensisGeorgi and has been shown to possess a potent inhibitory activity against viruses. However, the role of BA in anti-influenza virus has not been extensively studied, and the immunological mechanism of BA in antiviral activity remains unknown. Here, we observed that BA could protect mice from infection by influenza virus A/PR/8/34 (H1N1), associated with increasing IFN-γproduction, but presented no effects in IFN-γor IFN-γreceptor deficient mice. Further study indicated that BA could inhibit A/PR/8/34 replication through IFN-γin human PBMC. Moreover, BA can directly induce IFN-γproduction in human CD4+and CD8+T cells and NK cells, and activate JAK/STAT-1 signaling pathway. Collectively, BA exhibited anti-influenza virus A (H1N1) activityin vitroandin vivoas a potent inducer of IFN-γin major IFN-γproducing cells.

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1-Acyl-3-cyclooctylguanidines

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19801595 ◽

1980 ◽

Vol 45 (5) ◽

pp. 1595-1600 ◽

Cited By ~ 3

Author(s):

Jaroslav Sluka ◽

František Šmejkal ◽

Zdeněk Buděšínský

Keyword(s):

Influenza Virus ◽

Herpes Simplex ◽

Methyl Esters ◽

Antiviral Effect ◽

Influenza Virus A

On recation of cyclooctylamine with the sulfate of S-methylisothiourea cyclooctylguanidine was formed which was acylated with the methyl esters of 5-halogeno- and 3,5-dihalogeno-2-alkoxybenzoic acids. The 1-acyl-3-cyclooctylguanidine I-XVII formed were tested for their antiviral effect against the influenza virus A/NWS, A-PR8 and A2 Singapore, and further against the viruses NDV, herpes 2, vaccinia and WEE. In the in vivo test against the influenza virus A2 Singapore and herpes simplex 1-(5-bromo-2-dodecyloxybenzoyl)-3-cyclooctylguanidine is more active and less toxic than cyclooctylamine and 1-cyclooctylguanidine.

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Influenza virus carrying neuraminidase with reduced sensitivity to oseltamivir carboxylate has altered properties in vitro and is compromised for infectivity and replicative ability in vivo

Antiviral Research ◽

10.1016/s0166-3542(01)00215-7 ◽

2002 ◽

Vol 54 (2) ◽

pp. 79-88 ◽

Cited By ~ 129

Author(s):

J Carr ◽

J Ives ◽

L Kelly ◽

R Lambkin ◽

J Oxford ◽

...

Keyword(s):

Influenza Virus ◽

Oseltamivir Carboxylate

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Influenza virus hemagglutinin-specific cytotoxic T cell response induced by polypeptide produced in Escherichia coli.

Journal of Experimental Medicine ◽

10.1084/jem.162.2.663 ◽

1985 ◽

Vol 162 (2) ◽

pp. 663-674 ◽

Cited By ~ 29

Author(s):

A Yamada ◽

M R Ziese ◽

J F Young ◽

Y K Yamada ◽

F A Ennis

Keyword(s):

Influenza Virus ◽

Recombinant Dna ◽

Cytotoxic T Lymphocyte ◽

Nonstructural Protein ◽

T Cell Response ◽

Cytotoxic T Cell ◽

Protein Immunization ◽

Recombinant Dna Techniques

We have tested the abilities of various polypeptides of A/PR/8/34 (H1N1) virus, constructed by recombinant DNA techniques, to induce influenza virus-specific secondary cytotoxic T lymphocyte (CTL) responses. A hybrid protein (c13 protein), consisting of the first 81 amino acids of viral nonstructural protein (NS1) and the HA2 subunit of viral hemagglutinin (HA), induced H-2-restricted, influenza virus subtype-specific secondary CTL in vitro, although other peptides did not. Using a recombinant virus, the viral determinant responsible for recognition was mapped to the HA2 portion of c13 protein. Immunization of mice with c13 protein induced the generation of memory CTL in vivo. The CTL precursor frequencies of A/PR/8/34 virus- and c13 protein-immune mice were estimated as one in 8,047 and 50,312, respectively. These results indicate that c13 protein primed recipient mice, even though the level of precursor frequency was below that observed in virus-immune mice.

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Effect of Influenza Virus Proteins Modulate Hemostasis in vitro and in vivo

Biology Bulletin ◽

10.1023/b:bibu.0000007717.01890.98 ◽

2003 ◽

Vol 30 (6) ◽

pp. 596-602

Author(s):

I. N. Zhilinskaya ◽

L. A. Lyapina ◽

O. I. Kiselev ◽

I. P. Ashmarin

Keyword(s):

Influenza Virus ◽

Virus Proteins

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Natural and directed antigenic drift of the H1 influenza virus hemagglutinin stalk domain

Scientific Reports ◽

10.1038/s41598-017-14931-7 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 36

Author(s):

Christopher S. Anderson ◽

Sandra Ortega ◽

Francisco A. Chaves ◽

Amelia M. Clark ◽

Hongmei Yang ◽

...

Keyword(s):

Influenza Virus ◽

Viral Fitness ◽

Antigenic Drift ◽

Virus Infections ◽

Head Region ◽

Immune Pressure ◽

Stalk Domain ◽

Ha Protein

Abstract The induction of antibodies specific for the influenza HA protein stalk domain is being pursued as a universal strategy against influenza virus infections. However, little work has been done looking at natural or induced antigenic variability in this domain and the effects on viral fitness. We analyzed human H1 HA head and stalk domain sequences and found substantial variability in both, although variability was highest in the head region. Furthermore, using human immune sera from pandemic A/California/04/2009 immune subjects and mAbs specific for the stalk domain, viruses were selected in vitro containing mutations in both domains that partially contributed to immune evasion. Recombinant viruses encoding amino acid changes in the HA stalk domain replicated well in vitro, and viruses incorporating two of the stalk mutations retained pathogenicity in vivo. These findings demonstrate that the HA protein stalk domain can undergo limited drift under immune pressure and the viruses can retain fitness and virulence in vivo, findings which are important to consider in the context of vaccination targeting this domain.

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In VitroSusceptibility of Canine Influenza A (H3N8) Virus to Nitazoxanide and Tizoxanide

Veterinary Medicine International ◽

10.4061/2010/891010 ◽

2010 ◽

Vol 2010 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Laura V. Ashton ◽

Robert L. Callan ◽

Sangeeta Rao ◽

Gabriele A. Landolt

Keyword(s):

Influenza Virus ◽

Influenza A ◽

The United States ◽

Canine Influenza Virus ◽

Valuable Adjunct ◽

Canine Influenza ◽

The Impact ◽

H3n8 Virus

Infection of dogs with canine influenza virus (CIV) is considered widespread throughout the United States following the first isolation of CIV in 2004. While vaccination against influenza A infection is a common and important practice for disease control, antiviral therapy can serve as a valuable adjunct in controlling the impact of the disease. In this study, we examined the antiviral activity of nitazoxanide (NTZ) and tizoxanide (TIZ) against three CIV isolatesin vitro. NTZ and TIZ inhibited virus replication of all CIVs with 50% and 90% inhibitory concentrations ranging from 0.17 to 0.21 μMand from 0.60 to 0.76 μM, respectively. These results suggest that NTZ and TIZ are effective against CIV and may be useful for treatment of canine influenza in dogs but further investigation of thein vivoefficacy against CIV as well as the drug's potential for toxicity in dogs is needed.

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