Figure 4.

Effects of Eucalyptus oil treatment on MDM phagocytic ability against apoptotic bodies from the MCF7 human breast cancer cells. Apoptotic bodies (AB) were obtained from MCF7 breast carcinoma cells as described in Materials and Methods. The phagocytic activity of MDMs pre-treated for 24 h with 0.008% EO and of untreated controls was tested by adding to cell cultures the PI-stained apoptotic bodies (AB; red hue) in a ratio of about 5 AB/cell. MDMs pre-treated for 6 h with 0.1 µg/mL LPS were used as a positive control of macrophage activation. Samples were analyzed 1 h and 3 h after AB administration. (A) Confocal microscopy images, showing the AB uptake in untreated control and EO treated MDMs. Merged images with differential interference contrast, used to visualize cell morphology, are shown. Arrows point to internalized AB. Bar = 50 µm. (B,C) Quantitative assessment of MDM phagocytic activity obtained by counting the number of phagocytes, reported as percent of phagocytic cells (B), as well as the number of AB per cell (C). A minimum of 200 cells/sample were analyzed and the results are the mean ± SD from three independent experiments (n = 3). Significance (One-way ANOVA + Tukey multiple comparison test), * vs. CTR at the same time: ** p < 0.01, *** p < 0.001; # vs. LPS: # p < 0.05, ### p < 0.001; ns: not significant.