Immunogenicity and Protective Efficacy of a Single Intranasal Dose Vectored Vaccine Based on Sendai Virus (Moscow Strain) against SARS-CoV-2 Variant of Concern.

The mouse paramyxovirus Sendai, which is capable of limited replication in human bronchial epithelial cells without causing disease, is well suited for the development of vector-based intranasal vaccines against respiratory infections, including SARS-CoV-2. Using the Moscow strain of the Sendai virus, we developed a vaccine construct, Sen-Sdelta(M), which expresses the full-length spike (S) protein of the SARS-CoV-2 delta variant. A single intranasal delivery of Sen-Sdelta(M) to Syrian hamsters and BALB/c mice induced high titers of virus-neutralizing antibodies specific to the SARS-CoV-2 delta variant.

[Intranasal vaccine against COVID-19 based on a recombinant variant of the Sendai virus (Paramyxoviridae: ) strain Moscow].

Introduction: Intranasal vaccination using live vector vaccines based on non-pathogenic or slightly pathogenic viruses is the one of the most convenient, safe and effective ways to prevent respiratory infections, including COVID-19. Sendai virus is the best suited for this purpose, since it is respiratory virus and is capable of limited replication in human bronchial epithelial cells without causing disease. The aim of the work is to design and study the vaccine properties of recombinant Sendai virus, Moscow strain, expressing secreted receptor-binding domain of SARS-CoV-2 Delta strain S protein (RBDdelta) during a single intranasal immunization.

[Mucosal immunity and vaccines against viral infections].

Mucosal immunity is realized through a structural and functional system called mucose-associated lymphoid tissue (MALT). MALT is subdivided into parts (clusters) depending on their anatomical location, but they all have a similar structure: mucus layer, epithelial tissue, lamina propria and lymphoid follicles. Plasma cells of MALT produce a unique type of immunoglobulins, IgA, which have the ability to polymerize.

[The Challenges of Vaccine Development Against Betacoronaviruses: Antibody Dependent Enhancement and Sendai Virus as a Possible Vaccine Vector].

To design an effective and safe vaccine against betacoronaviruses, it is necessary to elicit a combination of strong humoral and cell-mediated immune responses as well as to minimize the risk of antibody-dependent enhancement of viral infection. This phenomenon was observed in animal trials of experimental vaccines against SARS-CoV-1 and MERS-CoV that were developed based on inactivated coronavirus or vector constructs expressing the spike protein (S) of the virion. The substitution and glycosylation of certain amino acids in the antigenic determinants of the S-protein, as well as its conformational changes, can lead to the same effect in a new experimental vaccine against SARS-CoV-2.

The Challenges of Vaccine Development against Betacoronaviruses: Antibody Dependent Enhancement and Sendai Virus as a Possible Vaccine Vector.

To design an effective and safe vaccine against betacoronaviruses, it is necessary to use their evolutionarily conservative antigenic determinants that will elicit the combination of strong humoral and cell-mediated immune responses. Targeting such determinants minimizes the risk of antibody-dependent enhancement of viral infection. This phenomenon was observed in animal trials of experimental vaccines against SARS-CoV-1 and MERS-CoV that were developed based on inactivated coronavirus or vector constructs expressing the spike protein (S) of the virion.

Directed evolution as a tool for the selection of oncolytic RNA viruses with desired phenotypes.

Viruses have some characteristics in common with cell-based life. They can evolve and adapt to environmental conditions. Directed evolution can be used by researchers to produce viral strains with desirable phenotypes.

[Oncolytic Paramyxoviruses: Mechanism of Action, Preclinical and Clinical Studies].

Preclinical studies demonstrate that a broad spectrum of human and animal malignant cells can be killed by oncolytic paramyxoviruses, which includes cells of ecto-, endo- and mesodermal origin. In clinical trials, significant reduction or even complete elimination of primary tumors and established metastases has been reported. Different routes of virus administration (intratumoral, intravenous, intradermal, intraperito-neal, or intrapleural) and single- vs.

Complete Genome Sequence of the Oncolytic Sendai virus Strain Moscow.

We report here the complete genome sequence of Sendai virus Moscow strain. Anecdotal evidence for the efficacy of oncolytic virotherapy exists for this strain. The RNA genome of the Moscow strain is 15,384 nucleotides in length and differs from the nearest strain, BB1, by 18 nucleotides and 11 amino acids.