CD4+ T Cells of Prostate Cancer Patients Have Decreased Immune Responses to Antigens Derived From SARS-CoV-2 Spike Glycoprotein

Effectiveness and Durability of mRNA Vaccine-Induced SARS-CoV-2-Specific Humoral and Cellular Immunity in Severe Asthma Patients on Biological Therapy

Coronavirus disease 2019 (COVID-19) vaccines effectively elicit humoral and cellular immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthy populations. This immunity decreases several months after vaccination. However, the efficacy of vaccine-induced immunity and its durability in patients with severe asthma on biological therapy are unknown. In this study, we evaluated the effectiveness and durability of mRNA vaccine-induced SARS-CoV-2-specific humoral and cellular immunity in severe asthma patients on biological therapy. The study included 34 patients with severe asthma treated with anti-IgE (omalizumab, n=17), anti-IL5 (mepolizumab, n=13; reslizumab, n=3), or anti-IL5R (benralizumab, n=1) biological therapy. All patients were vaccinated with two doses of the BNT162b2 mRNA vaccine with a 6-week interval between the doses. We found that this COVID-19 vaccination regimen elicited SARS-CoV-2-specific humoral and cellular immunity, which had significantly declined 6 months after receipt of the second dose of the vaccine. The type of biological treatment did not affect vaccine-elicited immunity. However, patient age negatively impacted the vaccine-induced humoral response. On the other hand, no such age-related impact on vaccine-elicited cellular immunity was observed. Our findings show that treatment of patients with severe asthma with biological therapy does not compromise the effectiveness or durability of COVID-19 vaccine-induced immunity.

COVID-19 vaccine development: milestones, lessons and prospects

With the constantly mutating of SARS-CoV-2 and the emergence of Variants of Concern (VOC), the implementation of vaccination is critically important. Existing SARS-CoV-2 vaccines mainly include inactivated, live attenuated, viral vector, protein subunit, RNA, DNA, and virus-like particle (VLP) vaccines. Viral vector vaccines, protein subunit vaccines, and mRNA vaccines may induce additional cellular or humoral immune regulations, including Th cell responses and germinal center responses, and form relevant memory cells, greatly improving their efficiency. However, some viral vector or mRNA vaccines may be associated with complications like thrombocytopenia and myocarditis, raising concerns about the safety of these COVID-19 vaccines. Here, we systemically assess the safety and efficacy of COVID-19 vaccines, including the possible complications and different effects on pregnant women, the elderly, people with immune diseases and acquired immunodeficiency syndrome (AIDS), transplant recipients, and cancer patients. Based on the current analysis, governments and relevant agencies are recommended to continue to advance the vaccine immunization process. Simultaneously, special attention should be paid to the health status of the vaccines, timely treatment of complications, vaccine development, and ensuring the lives and health of patients. In addition, available measures such as mix-and-match vaccination, developing new vaccines like nanoparticle vaccines, and optimizing immune adjuvant to improve vaccine safety and efficacy could be considered.

Antibody Responses to COVID-19 Vaccination in Cancer: A Systematic Review

INTRODUCTION

After the results of phase III vaccine studies became available, the leading oncology societies recommended two doses of COVID-19 vaccination to all patients with cancer with no specific recommendation for tumor type and active treatments. However, the data on the COVID-19 vaccine efficacy in cancer patients is limited due to exclusion of cancer patients from most vaccine clinical trials. Therefore, we systemically reviewed the available evidence evaluating the antibody responses in cancer patients.

METHODS

We conducted a systematic search from the Pubmed database and calculated risk differences (RD) and 95% confidence intervals (CI) to compare seroconversion rates between cancer patients and controls using the Review Manager software, version 5.3.

RESULTS

Our systematic search retrieved a total 27 studies and we included 17 studies with control arms in the analyses. Cancer patients had significantly lower seroconversion rates (37.3%) than controls (74.1%) (RD: -0.44, 95% CI: -0.52, -0.35, p<0.001) with first vaccine dose. After two doses, the seroconversion rates were 99.6% in control arm and 78.3% in cancer patients (RD: -0.19, 95% CI: -0.28, -0.10, p<0.001). The difference in seroconversion rates was more pronounced patients with hematologic malignancies (72.6%) (RD: -0.25, 95% CI: -0.27, -0.22, p<0.001) than patients with solid tumors (91.6%) (RD: -0.09, 95% CI: -0.13, -0.04, p<0.003) and patients in remission (RD: -0.10, 95% CI: -0.14, -0.06, p<0.001).

CONCLUSION

In conclusion, COVID-19 vaccine seroconversion rates were significantly lower in patients with hematological malignancies and patients under active treatment. Further research focusing on the approaches to improve vaccine efficacy and exploration of novel treatment options is urgently needed for these patients.

SARS-CoV-2 spike glycoprotein-reactive T cells can be readily expanded from COVID-19 vaccinated donors

Introduction

The COVID‐19 vaccine was designed to provide protection against infection by the severe respiratory coronavirus 2 (SARS‐CoV‐2) and coronavirus disease 2019 (COVID‐19). However, the vaccine's efficacy can be compromised in patients with immunodeficiencies or the vaccine‐induced immunoprotection suppressed by other comorbidity treatments, such as chemotherapy or immunotherapy. To enhance the protective role of the COVID‐19 vaccine, we have investigated a combination of the COVID‐19 vaccination with ex vivo enrichment and large‐scale expansion of SARS‐CoV‐2 spike glycoprotein‐reactive CD4⁺ and CD8⁺ T cells.

Methods

SARS‐CoV‐2‐unexposed donors were vaccinated with two doses of the BNT162b2 SARS‐CoV‐2 vaccine. The peripheral blood mononuclear cells of the vaccinated donors were cell culture‐enriched with T cells reactive to peptides derived from SARS‐CoV‐2 spike glycoprotein. The enriched cell cultures were large‐scale expanded using the rapid expansion protocol (REP) and the peptide‐reactive T cells were evaluated.

Results

We show that vaccination with the SARS‐CoV‐2 spike glycoprotein‐based mRNA COVID‐19 vaccine‐induced humoral response against SARS‐CoV‐2 spike glycoprotein in all tested healthy SARS‐CoV‐2‐unexposed donors. This humoral response was found to correlate with the ability of the donors' PBMCs to become enriched with SARS‐CoV‐2 spike glycoprotein‐reactive CD4⁺ and CD8⁺ T cells. Using an 11‐day REP, the enriched cell cultures were expanded nearly 1000‐fold, and the proportions of the SARS‐CoV‐2 spike glycoprotein‐reactive T cells increased.

Conclusion

These findings show for the first time that the combination of the COVID‐19 vaccination and ex vivo T cell large‐scale expansion of SARS‐CoV‐2‐reactive T cells could be a powerful tool for developing T cell‐based adoptive cellular immunotherapy of COVID‐19.