Evaluation of myeloid-derived suppressor cells (MDSCs) and natural killer (NK) cell cytotoxicity following COVID-19 vaccination

Abstract

Abstract The pandemic nature of coronavirus disease (COVID-19) has led to the global use of vaccines, but their effectiveness on innate immune cells has not been elucidated. Myeloid-derived suppressor cells (MDSCs) and natural killer (NK) cells have an important role in SARS-CoV-2 pathogenesis infection as well as vaccination. This study aimed to evaluate MDSC frequency and NK cell-mediated cytotoxicity in response to different types of COVID-19 vaccines. The results showed that MDSCs frequencies were significantly increased in both Sinopharm and Pfizer-BioNTech vaccinated groups compared to unvaccinated participants and those vaccinated with AstraZeneca. Concerning NK cytotoxicity level, a statistically significant increase was observed in all vaccinated participants compared to unvaccinated volunteers, with a statistical significant increase in the Pfizer-BioNTech group compared to other vaccinated groups. In addition, NK cytotoxicity level was significantly upregulated in vaccinated candidates who received 3 vaccine doses with a vaccination-sampling interval of ≤ 6 months. It can be concluded that the lowest frequency of MDSC was demonstrated in AstraZeneca-vaccinated participants, whilst the highest level of NK cytotoxicity was observed in mRNA Pfizer-BioNTech-vaccinated participants compared to their homologous counterparts. Graphical Abstract