Antiviral adsorption activity of porous silicon nanoparticles against different pathogenic human viruses.

New viral infections, due to their rapid spread, lack of effective antiviral drugs and vaccines, kill millions of people every year. The global pandemic SARS-CoV-2 in 2019-2021 has shown that new strains of viruses can widespread very quickly, causing disease and death, with significant socio-economic consequences. Therefore, the search for new methods of combating different pathogenic viruses is an urgent task, and strategies based on nanoparticles are of significant interest.

Immunization of Domestic Ducks with Live Nonpathogenic H5N3 Influenza Virus Prevents Shedding and Transmission of Highly Pathogenic H5N1 Virus to Chickens.

Wild ducks are known to be able to carry avian influenza viruses over long distances and infect domestic ducks, which in their turn infect domestic chickens. Therefore, prevention of virus transmission between ducks and chickens is important to control the spread of avian influenza. Here we used a low pathogenic wild aquatic bird virus A/duck/Moscow/4182/2010 (H5N3) for prevention of highly pathogenic avian influenza virus (HPAIV) transmission between ducks and chickens.

Immunization with live nonpathogenic H5N3 duck influenza virus protects chickens against highly pathogenic H5N1 virus.

Development of an effective, broadly-active and safe vaccine for protection of poultry from H5N1 highly pathogenic avian influenza viruses (HPAIVs) remains an important practical goal. In this study we used a low pathogenic wild aquatic bird virus isolate А/duck/Moscow/4182/2010 (H5N3) (dk/4182) as a live candidate vaccine. We compared this virus with four live 1:7 reassortant anti-H5N1 candidate vaccine viruses with modified hemagglutinin from either A/Vietnam/1203/04 (H5N1) or A/Kurgan/3/05 (H5N1) and the rest of the genes from either H2N2 cold-adapted master strain A/Leningrad/134/17/57 (rVN-Len and rKu-Len) or H6N2 virus A/gull/Moscow/3100/2006 (rVN-gull and rKu-gull).

Mass spectrometry analysis of influenza virus reassortant clones does not reveal an influence of other viral proteins on S-acylation of hemagglutinin.

Hemagglutinin (HA) of influenza virus is S-acylated with stearate at a transmembrane cysteine and with palmitate at two cytoplasmic cysteines. The amount of stearate varies from 35 (in avian strains) to 12% (in human strains), although the acylation region exhibits only minor or even no amino acid differences between HAs. To address whether matrix proteins and neuraminidase affect stearoylation of HA, we used mass spectrometry to analyze laboratory reassortants containing avian virus HA and the internal proteins from a human virus.

[The generation and characteristics of reassortant influenza A virus with H5 hemagglutinin and other genes from the apathogenic virus H6N2].

The experimental reassortant vaccine strain VN-gull (H5N2) containing H5 hemagglutinin (HA) with a removed polybasic site in the connecting peptide and other genes from the apathogenic H6N2 virus A/gull/Moscow/3100/2006 (gull/M) was obtained using a two-step protocol. At Step 1, the reassortant with HA of A/Vietnam/1203/04-PR8/ CDC-RG and other genes from cold-adapted A/Leningrad/17/47 (VN-Len) viruses was generated due to selection with antibody to H2N2 at 26 degrees C. At Step 2, the reassortant VN-gull was obtained by replacing all genes from Len with those from gull/M due to selection with antibody to H6N2 at 39 degrees C.