Background: The problem of identifying vaccine-specific T-cell responses is still a matter of debate. Currently, there are no universal, clearly defined, agreed upon criteria for assessing the effectiveness of vaccinations and their immunogenicity for the cellular component of immunity, even for healthy people. But for patients with inborn errors of immunity (IEI), especially those with antibody deficiencies, evaluating cellular immunity holds significant importance. Aim: To examine the effect of one and two doses of inactivated adjuvanted subunit influenza vaccines on the expression of endosomal Toll-like receptors (TLRs) on the immune cells and the primary lymphocyte subpopulations in patients with common variable immunodeficiency (CVID). Materials and methods: During 2018–2019, six CVID patients received one dose of a quadrivalent adjuvanted influenza vaccine; in 2019–2020, nine patients were vaccinated with two doses of a trivalent inactivated influenza vaccine. The proportion of key lymphocyte subpopulations and expression levels of TLRs were analyzed using flow cytometry with monoclonal antibodies. Results: No statistically significant alterations in the absolute values of the main lymphocyte subpopulations were observed in CVID patients before or after vaccination with the different immunization protocols. However, after vaccination, a higher expression of TLR3 and TLR9 in granulocytes, monocytes, and lymphocytes was found in those patients who received two vaccine doses rather than one single dose. Conclusion: This study marks the first instance of using a simultaneous two-dose vaccination, which is associated with an elevated level of TLR expression in the immune cells. Administration of the adjuvanted vaccines in CVID patients appears promising. Further research into their impact on innate immunity and the development of more effective vaccination regimens is warranted.

There are increasing data concerning changes in hematological (clinical) and biochemical blood tests in patients with COVID-19 infection, which indicate the severity of the manifestations of the infectious process. Coagulopathy often correlates with the severity of COVID-19 disease and the risk of death. In this regard, prediction of developing coagulopathy and its prevention remain quite relevant. The aim of our study was to identify differences in the content of platelets and D-dimer in patients with COVID-19. The study included cohorts of patients vaccinated against SARS-CoV-2, and those not immunized against this infection. A prospective, randomized, observational study of the patients’ response was performed in cohorts of 588/52.2% vaccinated (vaccinated) and 588/52.2% non-immunized (non-vaccinated) patients with diagnosed COVID-19 over the period from 23.06.2021 to 01.05.2022. The levels of blood platelets and D-dimer, as well as clinical outcomes of the disease in patients with COVID-19, were studied in dynamics on days 1-2, 5-6 and 10-12 of hospitalization. Upon admission, the normal value of the blood platelet counts did not differ between the compared groups, being 206.58 × 109 in vaccinated group and 204.85 × 109 in the unvaccinated group, respectively. a moderate increase in the concentration of D-dimer was noted in both groups upon admission, i.e., 2838.60 ng/mL in the group of vaccinated patients and 3242.08 ng/mL among the unvaccinated patients. In the course of the study, we have shown that the dynamics of D-dimer index in vaccinated versus non-immunized persons was similar according to the days of disease, showing an increase from the first day and a trend towards an higher values, starting from 5-6 days. At the same time, the dynamics in the vaccinated patients was somewhat less favorable than that of the non-immunized subjects. In the patients who were not immunized throughout the entire observation period, the platelet count exceeds the levels found in vaccinated subjects, thus suggesting higher risk of thrombosis and cytokine storm. The data obtained show that the dynamics of D-dimer and platelet counts in vaccinated and non-immunized people is similar on appropriate terms of the illness. However, the changes are more pronounced in vaccinated cohort, but it does not indicate a greater risk of adverse outcomes.

Measles has not yet been eradicated; therefore, its outbreaks are still reported throughout the world. Like any infection, measles is dangerous for immunocompromised patients. Levels of anti-measles IgG antibodies were measured in 157 patients aged 17 to 72, who were placed on the lung transplant waiting list. Measurements were undertaken by enzyme-linked immunosorbent assay (ELISA) using the VectoMeasles-IgG kit (Russia). The proportion of patients seronegative for measles was 19% (30/157). Correlation was detected between patients’ age and their levels of anti-measles antibodies, with higher proportions of patients having undetectable titers (25.5–28.9%) or low antibody levels (38.3–44.4%) in the young age groups (17–29 and 30–39 years old). There were no differences between male and female patients in levels of anti-measles antibodies or in the proportion of seronegative individuals. Analyses of antibody levels with regard to type of disease revealed the highest rate of seronegative results in cystic fibrosis patients (34.4%, 11/32). Overall, 19% of lung transplant candidates, mostly young people and cystic fibrosis patients, did not have protective immunity against measles.

Background: SARS-CoV-2 infection has raised concerns about altered immune responses, creating a need to evaluate influenza vaccine performance in the post-COVID period. This study aimed to compare the immunogenicity and safety of a quadrivalent inactivated subunit adjuvanted influenza vaccine in adults aged 18–85 years during the 2022–2023 season. Methods: A total of 144 adults were enrolled: group 1, aged 18–59 years (n = 124), and group 2, aged 60–85 years (n = 20). All received a quadrivalent inactivated subunit adjuvanted vaccine containing 5 μg of each influenza antigen and 500 μg of Azoximer bromide. IgG antibodies to vaccine strains were measured at baseline and days 30–32 using the hemagglutination inhibition assay. Participants were actively monitored for adverse events by telephone. Results: The Geometric Mean Fold Increase (GMFI) met the efficacy criteria in both age groups (≥2.5 for 18–59 years and ≥2.0 for 60–85 years), with no significant differences. The seroprotection rate reached accepted thresholds for most strains but was below criteria for B/Victoria in the 18–59 group (48%) and for B/Phuket in the 60–85 group (35%). Significant between-group differences were observed for B/Victoria (p = 0.01) and B/Phuket (p = 0.007). Seroconversion met criteria for all strains in younger adults, but for older adults, it was insufficient for B/Phuket (20%, below the ≥30% threshold; p = 0.05 vs. 18–59 years). Local reactions occurred in 24.2% and systemic in 11.3% of younger adults; in older adults, in 20% and 15%, respectively. All resolved spontaneously within 1–3 days. Conclusions: The quadrivalent adjuvanted influenza vaccine demonstrated acceptable immunogenicity and safety in adults aged 18–85 years despite potential post-COVID immune alterations.

The novel coronavirus infection (COVID-19) has a suppressive effect on innate immunity, which is a prerequisite for developing strategies to enhance this non-specific link as a preventive measure to protect against other respiratory infections during the ongoing circulation of mutating strains of the SARS-CoV-2 virus. Despite the currently developed and available preventive measures, it has been noted that in persons who have undergone COVID-19, repeated episodes of both coronavirus infection and diseases caused by other pathogens have been recorded. This review analyzes data from the biomedical literature and considers examples of health risks associated with continued infection with pathogens that cause respiratory tract pathologies. It also reflects the ways and approaches of possible preventive measures, the purpose of which is to prevent the development of pathologies of both the respiratory organs and other systems.

Background: Influenza vaccine is a tool for preventing infection and reducing exacerbations in patients with asthma and chronic obstructive pulmonary disease (COPD). Purpose of this study is to investigate dynamics of CRP and serum cytokines (IL-2, IL-6, IL-10, IL-17) in patients with asthma and COPD, as well as to perform a correlation analysis with the clinical parameters of the disease manifestation. Methods: The study included 34 patients with asthma, 20 patients with COPD vaccinated against influenza during a period of remission from 2 to 4 weeks, both groups being under a basic maintenance therapy, and 26 healthy individuals vaccinated with the trivalent polymer-subunit vaccine Grippol® Plus, containing 5 µg of influenza virus strains and 500 µg of azoximer bromide. Results: Observing patients with asthma and COPD, during a year after the vaccination, has revealed a significant reduction in exacerbations frequency (p < 0.05) and duration (p < 0.05) of the bronchial obstructive syndrome (BF). Before the vaccination the IL-6 level in patients with asthma had a direct moderate correlation with duration of exacerbations of the underlying disease (p < 0.05), along with the number of systemic corticosteroids courses during exacerbations (p < 0.05). In 12 months after the vaccination, while assessing cytokine profile of all study groups, a significant reduction in the level of IL-6 was observed, compared to the baseline values (p< 0.05). Conclusion: Conducted analysis of immunological, clinical, and functional parameters of patients with asthma and COPD has proven for influenza vaccine to be effective in BF patients.