Benralizumab affects NK cell maturation and proliferation in severe asthmatic patients

Introduction: The mechanism of action of benralizumab is determined by its afucosylated constant fragment that binds CD16a receptors on the membrane of natural killer cells. Here we analysed changes in Natural Killer and T-cells in Severe asthmatic patients, before and after benralizumab.Methods: Natural Killer and T-cell subsets were detected through multiparametric flow cytometry. The concen-trations of serum cytokines levels were detected through multiplex assay. Functional proliferation assay was performed in follow-up samples in severe asthmatic patients.Results: At baseline, severe asthmatic patients showed higher percentages of immature Natural Killer cells when compared with healthy controls. We demonstrate the proliferative capacity of these cells and their activation after benralizumab administration. Benralizumab shifted Natural Killer cell phenotypes towards maturity. Cor-relation between the Natural Killer cells and functional parameters and with steroid-sparing was observed.Conclusion: Together this data contributes to our understanding of the mechanisms of action of benralizumab in the resolution of inflammation in severe asthma patients.