Figure 7.

Transmigration and in vitro retention of MNP-loaded murine NK cells through the application of an EMF in flow chambers and analysis of their chemotactic response. (A) Representative images of murine NK cells, treated with NPMs or not, migrating over a monolayer of murine endothelial cells (SVEC-4 cell line), acquired through confocal microscopy. The upper panel represents the apical part of the monolayer, while the lower panel represents the basal part [murine NK cells (green), cytoskeleton (red)]. Scale: 100 μm. Quantification of the adhesion (left panel) and transmigration (right panel) exhibited by murine NK cells in the presence of increasing concentrations of MNPs through murine endothelial cells. The results shown (mean ± SD) are representative of three independent experiments, analyzing at least 50 fields per condition, *p < 0.05, ***p < 0.001. (B) Migratory capacity of murine NK cells after treatment with MNPs in response to a specific chemotactic gradient and in the presence or absence of an EMF in the same direction. The results of this test were normalized against a control well (in the absence of transwell assay). (C) Displacement of murine NK cells in the direction of the magnetic gradient (Y axis) after being treated with MNPs or not and exposed to different EMFs. Cell displacement was quantified by analyzing at least 100 cells per video using Imaris software. The results shown (mean ± SD) are representative of three or four independent experiments, *p < 0.05, ***p < 0.001.