[HIV Restriction Factor APOBEC3G and Prospects for Its Use in Gene Therapy for HIV].

The mechanisms for the protection of the human body from viral or bacterial agents are extremely diverse. In one such mechanism, an important role belongs to the cytidine deaminase APOBEC3 family, which is the factor of congenital immunity and protects the organism from numerous viral agents. One of the proteins of this family, APOBEC3G, is able to protect against Human Immunodeficiency Virus type 1 in the absence of viral protein Vif. In turn, Vif opposes APOBEC3G action, causing polyubiquity of the protein and degradation in the proteasome. The review describes possible ways to increase the anti-HIV activity of APOBEC3G, giving it resistance to viral protein Vif, as well as potential approaches to the use of modified APOBEC3G in gene therapy for HIV.

[INCLUSION OF SITE-SPECIFIC MUTATIONS INTO CONSERVATIVE SEG- MENTS OF PA-GENE RESULTS IN ATTENUATION OF VIRULENT INFLUENZA VIRUS STRAIN A/WSN/33].

AIM: Study the possibility of obtaining attenuated variants of influenza virus by including specially selected site-specific mutations into a conservative sequence of PA-gene (terminal segment of COOH-domain of the PA-gene) of a virulent strain. MATERIALS AND METHODS: A/ WSN/33 - a virulent strain of influenza virus was used in the study. Inclusion of site-specif- ic mutations into PA-gene of the A/WSN/33 virulent strain was carried out using a two-step mutation PCR. Cloning was carried out using GoldenGate reaction. 8-plasmid transfection system based on pHW2000 vector was used. Transformation was carried out in rubidium competent bacterial cells of DH5(α strain. Transfection was done using Lipofectamine LTX (Invitrogen) reagentin a 293T and MDCK cells' co-culture. RESULTS: Transfectants with F658A substitution in the COOH-domain of the PA-gene were shown to acquire ts-phenotype and sharply reduce the ability to reproduce in mice lungs. Introduction of F658A substitution into COOH-domain of the PA-gene in combination with introduction of ts-mutations from ca influenzavirus strains into the genome ofthe virulent strain resulted in obtaining transfectants that have phenotypic characteristics typical for live influenza vaccine candidates. CONCLUSION: The ability to obtain attenuated variants of influenza viruses by introducing spe- cially selected site-specific mutations into conservative sequence of the PA-gene is shown.

[GENETIC CHARACTERISTICS OF INFLUENZA A/H3N2 AND B VIRUSES THAT HAD CIRCULATED IN RUSSIA IN 2013 - 2015].

AIM: Establish genetic characteristics, carry out phylogenetic analysis and determination of molecular markers of resistance to etiotropic preparations against influenza A/H3N2 and B viruses that had circulated in Russia in 2013 - 2015. MATERIALS AND METHODS: 80 biological samples containing influenza A/H3N2 virus RNA and 31 samples containing influenza B virus RNA were studied. Sequencing of PCR fragments was carried out inABI-3 100 PRIZMTM GeneticAnalyzer (AppliedBiosystems, USA) and using MiSeq (Illumina, USA). Data treatment and analysis was carried out using CLC v.3.6.5., DNASTAR and BioNumerics v.6.5. programs. RESULTS: In 2013 -2014 A/Texas/50/2012-like-clade 3C.3 influenza A/H3N2 viruses dominated, 10% belonged to subclade 3C.2a and 10% - to 3C.3b. Most of the viruses (8 1%) of 2014 - 2015 were of 3C.2a clade, the portion of viruses belonging to 3C.3b and 3C.3a was 9 and 10%. Yamagata-like viruses predominated among the studied influenza B viruses, only 1 virus of 2014 - 2015 belonged to Victoria lineage, 1 reassortant of Yamagata and Victoria lineages was detected. Rimantadine- resistance mutationS3 lN(M2 protein) was detected in all the influenza A/H3N2 viruses. Mutations determining resistance to oseltamivir (NA gene) were not detected in influenza A/H3N2 and B viruses. CONCLUSION: Increase of influenza morbidity in 2014 - 2015 was determined by the emergence of influenza A/H3N2 and B viruses, antigenically distinct from those that had circulated previously and those included into the vaccine, thus resulting in the WHO decision to change A/ H3N2 and B components of the 2015 - 2016 vaccine: Simultaneous circulation of 2 lineages of influenza B virus and emergence of their reassortants gives evidence on the necessity of use of quadrivalent vaccines, containing both lineages.

Immunogenic epitope prediction to create a universal influenza vaccine.

Influenza virus is one of the most rapidly evolving human pathogens and causes significant morbidity and mortality worldwide. This feature enables the virus to avoid natural or vaccine-induced immunity. For this reason, there is an intensive search for new approaches to create a universal influenza vaccine. Here, we propose pipelines based on modern prediction algorithms that allowed us to select 10 B-cell epitopes, 10 CD8+ T-cell epitopes and 6 CD4+ T-cell epitopes from influenza viruses that were characterized by high conservation and antigenicity. These epitopes could be used to create universal vaccines against influenza viruses. In addition, the scripts used in these pipelines are universal and can be used to select epitopes from other pathogens.

Application of real-time PCR to significantly reduce the time to obtain recombinant MVA virus.

Obtaining a pure recombinant Modified Vaccinia Ankara (MVA) virus is a multistage, time-consuming procedure. We describe a novel single-tube real-time PCR which enables determination of the amount of wild type and recombinant viruses and their ratio in plaques. Use of the real-time PCR significantly reduce the time and efforts needed to obtain purified recombinant MVA. The new approach has been applied to generate recombinant MVAs encoding different SARS-COV-2 antigens.