MR Detection of LPS-Induced Neutrophil Activation using Mannan-Coated Superparamagnetic Iron Oxide Nanoparticles

Purpose The purpose of this study was to investigate the potential of the phagocytic activity of lipopolysaccharide (LPS) induced neutrophils that are mannan coated with superparamagnetic iron oxide nanoparticles (M-SPION). Procedures Human neutrophils were divided into control and LPS groups. The neutrophils were labeled with M-SPION and dextran-coated SPION. After labeling of M-SPION, the mean signal intensity (SI) of the LPS group was significantly lower than that of the control group. Results The labeling of both control and LPS groups with M-SPION showed significantly lower SI than those labeled with D-SPION. After labeling with M-SPION, the intracellular iron uptake of neutrophil in Prussian blue staining was markedly demonstrated in the LPS group, but not in the control group. M-SPION was more effective than D-SPION in the labeling of neutrophils in vitro . Conclusions The in vitro labeling technique of LPS neutrophil with M-SPION on MR imaging could be developed into a diagnostic method of LPS-induced neutrophils.