Lyudmila Vasilievna Kolobukhina

Production of the recombinant hemagglutinin protein of the swine influenza virus A/H1N1 and analysis of its physicochemical and antigenic properties

Introduction. Predisposition to different courses of the infectious process is largely associated with the polymorphisms in human genome, especially in genes encoding proteins of the immune system. In the early stages of influenza infection such components of innate immunity as interferons I (α/β) and III (λ) type play a significant role in limiting virus replication. The aim of the work was to investigate associations of single nucleotide polymorphism in IFNL3 (rs8099917 T/G) and IFNL4 (rs12979860 C/T) genes with different course of influenza, and identify genetic markers of influenza complicated by community-acquired pneumonia. The genes noted above affect the production of interferon-λ3, which is involved in restriction of the viral replication. Materials and methods. Samples from 456 patients with mild (n = 150), moderate (n = 173), and severe (n = 133) influenza were studied. The viral RNA was detected by reverse transcription and polymerase chain reaction (RT-PCR). Polymorphisms in IFNL3 (rs8099917 T/G) and IFNL4 (rs12979860 C/T) genes was detected by PCR. Statistical analysis was performed using SNPStats software. Results. Patients with the C/T or T/T genotype of IFNL4 gene (rs12979860 C/T) were more likely to have pneumonia than those with the C/C genotype (OR 2.47 (1.31–4.63); p = 0.0044; q = 0.0059). The presence of one T allele increased the risk of developing pneumonia (OR 2.02 (1.05–4.02); p = 0.006; q = 0.008). In the presence of the T/T genotype, the risk increased more than twofold: OR 2.14 (1.31–3.48). Analysis of the SNP of IFNL3 gene (rs8099917 T/G) revealed a weak association of the G allele with pneumonia (OR 1.86 (1.04–3.31); p = 0.03; q = 0.045). Conclusion. Genetic markers of increased risk of community-acquired pneumonia in influenza include the presence of the T allele in IFNL4 gene (rs12979860 C/T) and, to a lesser extent, the G allele in IFNL3 gene (rs8099917 T/G). Patients carrying these alleles have an increased risk of developing pneumonia, especially in old age.

Ebola virus disease (EVD) is one of the most dangerous and lethal diseases affecting humans. There are several licensed vaccines against EVD, but it remains one of the priority diseases for research and development of effective vaccines. A double-blind randomized placebo-controlled trial was performed to evaluate safety and immunogenicity of rVSV- and rAd5-vectored vaccine “GamEvac-Combi” in healthy adults of both sexes between 18 and 60 years. Safety and immunogenicity were assessed during the observation period of 12 months. Immunogenicity was assessed with GP-specific ELISA, IFN-γ ELISA, and plaque pseudoneutralization assay. Vaccinated participants showed marked GP-specific IFN-γ response at day 28 and neutralizing response at day 42 (GMT = 32.6, seroconversion rate 96.3%). GP-specific IgG antibody levels in vaccinated participants peaked at day 42 (GMT = 9345) and persisted for a year after vaccination (GMT = 650). The vaccine showed favorable safety profile and induced robust cell-mediated immune response and strong humoral immune response that lasts at least for a year from the start of vaccination. The study was funded by the Ministry of Health of Russian Federation; GamEvac-Combi ClinicalTrials.gov number, NCT03072030 , Pan African Clinical Trial Registry PACTR201702002053400.

The purpose of this work was to determine the characteristics of the circulation of various viral respiratory pathogens during the epidemic season 2022–2023 against the background of the ongoing evolutionary variability of SARS-CoV-2. Materials and methods. The article uses methods used in «traditional» and «hospital» epidemiological surveillance of acute respiratory viral infections. Results and discussion. The period from October 2022 to September 2023 was characterized by early and high activity of influenza A(H1N1)pdm09 virus, which was replaced by influenza B virus. The antigenic and genetic properties of strains were closely related to influenza vaccines viruses recommended by WHO experts for the current season. The effectiveness of influenza vaccines was confirmed (75.0%). All of the studied influenza A(H1N1)pdm09, A(H3N2) and B epidemic strais retained sensitivity to drugs with antineuraminidase activity. The structure and share of other ARVI pathogens have changed somewhat compared to the previous season: There was a tendency to increase the activity of HAdV and HMPV; almost equivalent activity of HRsV, HRV, HCoV and HBoV; and a decrease in HPIV activity. At the same time, the frequency of other ARVI pathogens did not reach the indicators of the pre-pandemic COVID-19 period. The rationale for updating the composition of influenza vaccines for the countries of the Northern Hemisphere in the 2023–2024 season is given.

Introduction. COVID-19 is characterized by a varied clinical course. The aim of the work was to identify associations of SNPs of hemostatic system genes with COVID-19. Materials and methods. DNA was isolated from patients (n=117) and healthy participants (n=104). All infected patients were divided into 3 groups, depending on disease severity assessment, which was appreciated by NEWS2. Another group consisted of participants, who had asymptomatic infection in the past. Determination of SNPs of the genes FGB (-455 G/A), FII (20210 G/A), FV (1691 G/A), FVII (10976 G/A), FXIIIA1 (103 G/T), ITGA2 (807 C/T), ITGB3 (1565 T/C), SERPINE1 (-675 5G/4G) were performed by PCR using the “Genetics of Hemostasis” kit (“DNA-Technology”, Russia). Results. In analyzed SNPs, no significant differences were detected between the group of infected patients and healthy participants. But significant association was revealed in gene SERPINE1 (-675 5G/4G), when patient groups, differing in the disease severity, were analyzed relative to the group of participants with asymptomatic infection (p=0.0381; p=0 .0066; p=0.0009). It was found, that as COVID-19 severity scores increased, the proportion of 5G allele of gene SERPINE1 decreased, and the proportion of the 4G allele increased (p=0.005; p=0.009; p=0.0005). Similar processes were observed for genotypes 5G/5G and 4G/4G. Discussion. The gene SERPINE1 (-675 5G/4G) is associated with the severity of COVID-19. Conclusion. For the first time, it was discovered that 5G/5G genotype of gene SERPINE1 (-675 5G/4G) can be a marker of a milder course of COVID-19, and the 4G/4G genotype as a more severe one.

BACKGROUND: This study was conducted to determine the characteristics of various viral respiratory pathogens spreading during the epidemic season 20212022 and the frequency of co-infection with SARS-CoV-2 and influenza. AIM: To assess the development of the influenza epidemic and frequency of cases of co-infection with respiratory pathogens in patients with acute respiratory viral infections between 2021 and 2022. MATERIALS AND METHODS: Traditional and hospital epidemiological surveillance methods for acute respiratory viral infections were used. RESULTS: The epidemic season of 20212022 was characterized by the early activity of the influenza A(H3N2) virus and the emergence and rapid spread of the omicron variant of SARS-CoV-2. The distribution of different respiratory pathogens during the epidemic season 20212022 was clearly traced: SARS-CoV-2 (18.8%) was predominant, followed by influenza viruses (10.6%) and pathogens of other acute respiratory viral infections (0.43.7%). With respect to influenza A (H3N2) and B viruses, the heterogeneity of their populations and drift variability in relation to vaccine strains were noted. DISCUSSION: The frequency of co-infection with various respiratory pathogens was low, i.e., it was no more than 0.1%according to traditional surveillance, and no more than 9.2% in the hospital surveillance. The rationale for updating the composition of influenza vaccines for the countries in the Northern Hemisphere for 20222023 season was identified. CONCLUSION: At present, early diagnosis of influenza is important given the availability of effective drugs with a direct mechanism of action for the prevention and treatment of this pathogen. Timely use of anti-influenza drugs will reduce the risks of a severe course, complications, and death, including co-infection with SARS-CoV-2.

Introduction. The study of the mechanisms of transmission of the SARS-CoV-2 virus is the basis for building a strategy for anti-epidemic measures in the context of the COVID-19 pandemic. Understanding in what time frame a patient can spread SARS-CoV-2 is just as important as knowing the transmission mechanisms themselves. This information is necessary to develop effective measures to prevent infection by breaking the chains of transmission of the virus. The aim of the work is to identify the infectious SARS-CoV-2 virus in patient samples in the course of the disease and to determine the duration of virus shedding in patients with varying severity of COVID-19. Materials and methods. In patients included in the study, biomaterial (nasopharyngeal swabs) was subjected to analysis by quantitative RT-PCR and virological determination of infectivity of the virus. Results. We have determined the timeframe of maintaining the infectivity of the virus in patients hospitalized with severe and moderate COVID-19. Based on the results of the study, we made an analysis of the relationship between the amount of detected SARS-CoV-2 RNA and the infectivity of the virus in vitro in patients with COVID-19. The median time of the infectious virus shedding was 8 days. In addition, a comparative analysis of different protocols for the detection of the viral RNA in relation to the identification of the infectious virus was carried out. Conclusion. The obtained data make it possible to assess the dynamics of SARS-CoV-2 detection and viral load in patients with COVID-19 and indicate the significance of these parameters for the subsequent spread of the virus and the organization of preventive measures.

Relevance. The long-term leadership of ARVI pathogens determines their significance in the damage caused to both health and the economy of the country. Aim. To identify the features of the structure of ARVI during the emergence and widespread spread of SARS-CoV-2. Materials and methods. The article uses methods used in epidemiological surveillance of acute respiratory viral infections. Results and discussion. The results of the diagnostic available ARVI pathogens monitoring during epidemic seasons 2018-2021 are presented. The tendency of greater engagement of aged group 15 y.o. and older in epidemic process by morbidity and hospitalization due to SARI was shown. 49 818 nasal swabs from patients with influenza infection, 36 044 – with ARVI and 59 062 – with SARS-CoV-2 were tested. The top three in the structure of ARVI were INF, HEV-D and HRSV (in the 2018–2019 season); INF, SARS-CoV-2 and HEV-D (2019–2020); SARS-CoV-2, HEV-D and HPIV/HCoV (2020–2021). The activity of viral pathogens also differed: for HPIV, HAdV, HEV-D, HMPV, a decrease in activity was noted during the appearance of SARS-CoV-2 (2019–2020) and some of its growth in the following season; in relation to HRSV and INF - a decrease in activity during the last two seasons, and for INF – extremely low activity in the 2020-2021 season; the activity of seasonal HCoV even increased slightly. The data of genetic analyses of SARS-CoV-2 positive samples showed the heterogeneity of its population with a representative of variants (Alfa, Delta) as well as endemic for Russia and Moscow variants only. The recommended composition of influenza virus vaccines for use in the 2021–2022 northern hemisphere influenza season and in the 2022 southern hemisphere influenza season are presented due to their drift changeability. Conclusions. SARS-CoV-2 was influenced by the activity of ARVI pathogens with the almost complete displacement of influenza viruses from the circulation in the period 2020–2021.

Introduction. The increase in the incidence of whooping cough in children and adults of different age groups justifies the need for their revaccination and the development of new, acceptable for these purposes. This work is devoted to substantiating the design of a clinical trial and describing the results of a comparative study of the safety and tolerability of the drug "GamLPV" with two-fold intranasal administration to healthy adult volunteers using two methods. The choice of the scheme and method of administration of the drug is justified. The serological structure of the population of adults aged 18–40 years living in Moscow and the Moscow region is characterized.Aim. Determination of the safety and tolerability of the drug with a double intranasal administration of the vaccine by drip method and spraying through an actuator.Materials and methods. A randomized placebo-controlled trial included 50 healthy male and female volunteers aged 18 to 40 years who met the inclusion criteria. The volunteers were divided into 2 groups of 25 people: a drip method of administration and spraying through an "actuator". By both methods, the drug was administered twice with an interval of 60 days.Results and discussion. Serological analysis of the population of healthy volunteers at the prescreening stage justified the inclusion in the study of volunteers containing anti-pertussis antibodies in the blood (IgG ≤40 Ed/ml). A comparison of the results of preclinical studies on an experimental model of non-human monkeys and the first phase of a clinical study of GamLPV allowed us to propose two methods of double administration of the drug as a promising vaccination scheme for volunteers. A comparative randomized study shows the safety of using the proposed scheme for vaccination of adult volunteers.Conclusions. Both proposed methods of double administration can be used to plan a multicenter study to research the immunogenicity and protective activity of GamLPV.

The maximum incidence rates of measles were recorded on the eve of the development of the COVID-19 pandemic in 2019 in many countries of the world, including Russia. One of the features of the epidemic process of this infection in the period from 2011 to 2019 was the involvement of employees of medical organizations (MO) with the formation of large foci. Current features for the development of the measles epidemic situation can be assessed using serological studies. Aim: to assess the epidemiological features of measles in medical workers in Moscow, including by assessing the prevalence of specific IgG antibodies to the measles virus using the example of an infectious disease’s hospital in Moscow. Materials and methods. Using data from state reports on the sanitary and epidemiological well-being of the population in Moscow and form No. 2 of the Federal State Statistical Observation «Information on Infectious and Parasitic Diseases». To study the strength of immunity against measles by the method of enzyme-linked immunosorbent assay (ELISA) using test systems «Vecto-measles IgG» (CJSC «Vector-Best», Russia), 191 blood serum samples from the collection of the Department of Epidemiology of the National Research Center for Epidemiology were examined and Microbiology named after Honorary Academician N. F. Gamaleya (Moscow), taken from the employees of the infectious hospital of the city of Moscow (aged 22 to 65 years) with a different vaccination history. Positive (seropositive) was considered the result of a study of the level of IgG antibodies to measles virus more than 0.18 IU / ml. Results. A feature of the epidemic process of measles in Moscow (for the period from 2014 to 2020) was the annual (except for 2016) registration of measles cases among medical workers and hospital patients of various profiles (in 2019–2020, only among patients). Reasonable doubts about the reliability of the vaccination coverage of the population according to official statistics (exceeds the level of 95 % since 2013), including medical workers, arise due to the availability of data on the previous vaccination in some cases of measles. Measles vaccination data were recorded in 28 people (4.7 %) out of 191 surveyed. In two of them, antibodies to the measles virus could not be detected, and the median of their level in seropositive individuals was 1.75 IU / ml (0.5; 3.0). 10 health workers had a history of measles in the past, which was confirmed by serological examination (the level of IgG antibodies was higher than 3.3 IU / ml). 152 people (79.6 %) had no information about vaccination and measles in the past. Among them, eight people were seronegative (5.3 %), and the level of antibodies in the seropositive was higher than in the vaccinated, and amounted to 2.4 IU / ml [0.74; 3.68]. Conclusion. It was found that the proportion of seronegative among the surveyed individuals did not exceed 7 %. However, the predominance of individuals with a low level of immunity, both among vaccinated and unvaccinated individuals, indicates the need for periodic serological studies for the timely detection of seronegative individuals.