Effect of cerium and selenium nanoparticles on functional activity of neutrophils in vitro

Abstract

Abstract: Colloidal solutions of cerium and selenium nanoparticles were synthesized using the laser ablation method in deionized water. The resulting nanoparticle samples had a monomodal size distribution. The studied nanoparticles at a concentration of 1011 NPs/ml inhibit the peroxidase activity of neutrophil myeloperoxidase by approximately 10–15%. At the same time, the average fluorescence intensity of neutrophils, which exhibit both CD11b and CD66b on their surface, increases, which is a sign of degranulation of specific and gelatinase granules, as well as secretory vesicles. The studied particles of cerium and selenium have the ability to initiate secretory degranulation of neutrophils in a dose-dependent manner. After the addition of cerium nanoparticles to neutrophils, an increase in the production of hydrogen peroxide by neutrophils was recorded. At the same time, the assembly of NADPH oxidase was probably activated in neutrophils after they absorbed the nanoparticles. It has been shown that cerium and selenium nanoparticles are capable of initiating the formation of neutrophil extracellular traps. In general, the data obtained suggest that cerium nanoparticles in the considered range of concentrations contribute to a more pronounced activation of neutrophils under in vitro conditions compared to selenium nanoparticles. Keywords: NPs; selenium nanoparticles; cerium nanoparticles; neutrophils; immunomodulation; degranulation; NETs formation; netosis; NADPH oxidase activity; pro-oxidant