Humoral and cellular immune response to second and third severe acute respiratory syndrome coronavirus 2 mRNA vaccine in patients with plasma cell dyscrasia.

BACKGROUND: The recently developed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine has a short history of use and further information is needed regarding its efficacy, especially in immunocompromised conditions, such as plasma cell dyscrasia (PCD). METHODS: We retrospectively measured serum SARS-CoV-2 antibodies against the spike protein (S-IgG) after the second and third mRNA vaccine doses (doses 2 and 3, respectively) in 109 patients with PCD. We evaluated the proportion of patients with an adequate humoral response (defined as S-IgG titers ≥300 antibody units/mL). RESULTS: Although active anti-myeloma treatments prior to vaccination had a significantly negative impact on adequate humoral response, specific drug subclasses including immunomodulatory drugs, proteasome inhibitors, and monoclonal antibodies were not negatively associated, except for B-cell maturation antigen-targeted therapy. Dose 3 (booster vaccination) led to significantly higher S-IgG titers and more patients acquired an adequate humoral response. Furthermore, evaluation of vaccine-induced cellular immune response in patients using T-spot Discovery SARS-CoV-2 kit, revealed an enhanced cellular immune response after Dose 3. CONCLUSIONS: This study highlighted the significance of booster SARS-CoV-2 mRNA vaccination in patients with PCD with respect to humoral and cellular immunity. Moreover, this study highlighted the potential impact of certain drug subclasses on vaccine-induced humoral immune response.

A third dose SARS­CoV­2 BNT162b2 mRNA vaccine results in improved immune response in hemodialysis patients.

Background: The hemodialysis (HD) population has been a vulnerable group during the coronavirus disease 2019 (COVID-19) pandemic. Advanced chronic kidney disease with uremia is associated with weaker immune response to infections and an attenuated response to vaccines. The aim of this study was to study the humoral and cellular response to the second and third doses of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS­CoV­2) BNT162b2 mRNA vaccine in HD patients and to follow the response over time. Methods: The patients received their first two vaccine doses from 28 December 2020 within a 4-week interval and the third dose in September 2021 and were followed-up for humoral and cellular immune response at 1) 7-15 weeks and 2) 6-8 months after dose two (no t-cell reactivity measured), and 3) 3 weeks and 4) 3 months after dose three. Fifty patients were initially enrolled, and 40 patients were followed during the entire study. Levels of COVID-19 (SARS-CoV-2) IgG antibody against the Spike antigen (anti-S) and T-cell reactivity testing against the Spike protein using Enzyme-Linked ImmunoSpot (ELISPOT) technology were evaluated. Results: IgG antibodies to anti-S were detected in 35 (88%) of the 40 patients 7-15 weeks after vaccine dose two, 31 (78%) were positive, and 4 (10%) borderline. The median anti-S titer was 606 Abbott Units/milliliter (AU/mL) (interquartile range [IQR] 134-1,712). Three months after the third dose, anti-S was detected in 38 (95%) of 40 patients (P < 0.01 compared to after dose two), and the median anti-S titer was 9,910 AU/mL (IQR 2,325-26,975). Cellular reactivity was detected in 22 (55%), 34 (85%), and 28 (71%) of the 40 patients, and the median T-cell response was 9.5 (IQR 3.5-80), 51.5 (14.8-132), and 19.5 (8.8-54.2) units, respectively, for 6-8 months after dose two, 3 weeks, and 3 months after dose three. Conclusions: Our data show that a third dose of SARS­CoV­2 BNT162b2 mRNA vaccine gives a robust and improved immunological response in HD patients, but a few patients did not develop any anti-S response during the entire study, indicating the importance to monitor the vaccine response since those who do not respond could now be given monoclonal antibodies if they contract a COVID-19 infection or in the future antivirals.

On the Issue of Evaluating the Effectiveness of Vaccination of Employees of Medical Organizations against COVID-19

Relevance. Active mass vaccination of the population against a new COVID-19 is being carried out on the territory of the Russian Federation, which is recognized as a priority strategy for the country's healthcare for the near and long-term periods. One of the main risk groups that are subject to priority vaccination is medical workers. Aims. To evaluate the effectiveness of vaccination of medical organizations ' employees against COVID-19 based on the results of a 6-month prospective follow-up. Materials and methods. The observation group consisted of 356 employees of a medical organization who were vaccinated against COVID-19 with the drug «Gam-Covid-Vac» from December 2020 to April 2021. The effectiveness of vaccination of employees was evaluated by the coefficient of IgG positivity to SARS-CoV-2 by solid-phase enzyme immunoassay 3 weeks after the first administration and 3–4 weeks after the second administration of the vaccine and then 1 time per month. Employees who were revaccinated after 5–6 months. After the initial vaccination, they were examined 10–14 days after the introduction of the first component «Gam-CovidVac». A total of 1921 serum samples were studied. A specific T-cell immune response was determined in two study participants without seroprotection after administration of two components of the «Gam-Covid-Vac» vaccine and eight employees with the elimination of IgG antibodies 4–5 months after vaccination using ELISPOT technology. In addition, 92 blood serum samples of 32 employees from the observation group were examined for specific antibodies to adenovirus by indirect enzyme immunoassay. From December 2020 to June 2021, the study participants were subjected to dynamic clinical observation, once a week they were examined by PCR to detect SARS-CoV-2 RNA in smears from the pharynx and nose (a total of 5696 samples). Results. After the completed course of immunization, the formation of both a humoral (in 99.4% of cases) and cellular immune response (100% among the studied samples) was confirmed. In the next 6 months after vaccination, cases of coronavirus infection were registered in 4.8% of those vaccinated, including 1 person – in the first month after vaccination and 16 – 3–5 months after vaccination. In all cases, the disease occurred in the form of an acute respiratory infection of mild or moderate severity and was characterized by a shorter period of virus isolation compared to similar data on the persistence of the virus in unvaccinated patients (15 days in vaccinated compared to 22 days in unvaccinated). It was found that the presence of immunity to adenovirus infection during vaccination with the drug «Gam-Covid-Vac» did not affect the possibility of forming an immune response to COVID-19. In the group of persons re-vaccinated with the first component of «Gam-Covid-Vac» after 5–6 months. after the initial vaccination, an immune response was received during the follow-up period. Conclusion. Thus, according to the results of the study, a high immunological and epidemiological effectiveness of vaccination against COVID-19 with the drug «Gam-Covid-Vac» was established in a group of medical workers, and the effectiveness and safety of the administration of a booster dose of the vaccine after primary vaccination was also shown. Keywords: coronavirus infection, COVID-19, vaccination, «Gam-Covid-Vac», medical workers, humoral and cellular immune response No conflict of interest to declare. © 2022, Numikom. All rights reserved.

Higher SARS-CoV-2 Spike Binding Antibody Levels and Neutralization Capacity 6 Months after Heterologous Vaccination with AZD1222 and BNT162b2.

Within a year after the emergence of SARS-CoV-2, several vaccines had been developed, clinically evaluated, proven to be efficacious in preventing symptomatic disease, and licensed for global use. The remaining questions about the vaccines concern the duration of protection offered by vaccination and its efficacy against variants of concern. Therefore, we set out to analyze the humoral and cellular immune responses 6 months into homologous and heterologous prime-boost vaccinations. We recruited 190 health care workers and measured their anti-spike IgG levels, their neutralizing capacities against the Wuhan-Hu-1 strain and the Delta variant using a surrogate viral neutralization test, and their IFNγ-responses towards SARS-CoV-2-derived spike peptides. We here show that IFNγ secretion in response to peptide stimulation was significantly enhanced in all three vaccination groups and comparable in magnitude. In contrast, the heterologous prime-boost regimen using AZD1222 and BNT162b2 yielded the highest anti-spike IgG levels, which were 3-4.5 times more than the levels resulting from homologous AZD1222 and BNT162b2 vaccination, respectively. Likewise, the neutralizing capacity against both the wild type as well as the Delta receptor binding domains was significantly higher following the heterologous prime-boost regimen. In conclusion, our results suggest that mixing different SARS-CoV-2 vaccines might lead to more efficacious and longer-lasting humoral protection against breakthrough infections.

Humoral and cellular immunity to SARS-CoV-2 vaccination in renal transplant versus dialysis patients: A prospective, multicenter observational study using mRNA-1273 or BNT162b2 mRNA vaccine.

BACKGROUND: Dialysis and kidney transplant patients are vulnerable populations for COVID-19 related disease and mortality. METHODS: We conducted a prospective study exploring the eight week time course of specific cellular (interferon-γ release assay and flow cytometry) or/and humoral immune responses (ELISA) to SARS-CoV-2 boost vaccination in more than 3100 participants including medical personnel, dialysis patients and kidney transplant recipients using mRNA vaccines BNT162b2 or mRNA-1273. RESULTS: SARS-CoV-2-vaccination induced seroconversion efficacy in dialysis patients was similar to medical personnel (> 95%), but markedly impaired in kidney transplant recipients (42%). T-cellular immunity largely mimicked humoral results. Major risk factors of seroconversion failure were immunosuppressive drug number and type (belatacept, MMF-MPA, calcineurin-inhibitors) as well as vaccine type (BNT162b2 mRNA). Seroconversion rates induced by mRNA-1273 compared to BNT162b2 vaccine were 97% to 88% (p < 0.001) in dialysis and 49% to 26% in transplant patients, respectively. Specific IgG directed against the new binding domain of the spike protein (RDB) were significantly higher in dialysis patients vaccinated by mRNA-1273 (95%) compared to BNT162b2 (85%, p < 0.001). Vaccination appeared safe and highly effective demonstrating an almost complete lack of symptomatic COVID-19 disease after boost vaccination as well as ceased disease incidences during third pandemic wave in dialysis patients. CONCLUSION: Dialysis patients exhibit a remarkably high seroconversion rate of 95% after boost vaccination, while humoral response is impaired in the majority of transplant recipients. Immunosuppressive drug number and type as well as vaccine type (BNT162b2) are major determinants of seroconversion failure in both dialysis and transplant patients suggesting immune monitoring and adaption of vaccination protocols.