Fig 6. 4T1-conditioned macrophages exhibit increased phagocytosis of E. coli bioparticles.

BMDMs were treated for 24 h with 4T1- or HC11-conditioned medium (CM). BMDMs were then washed with PBS and incubated for 2 h with E. coli bioparticles, which fluoresce only under acidic conditions present in endosomes. E. coli phagocytosis was determined by measuring BMDM fluorescence by flow cytometry. As a negative control, BMDMs were pre-treated for 1 h with actin polymerization inhibitor cytochalasin D (10 μM) prior to the addition of E. coli bioparticles. Phagocytic activity was normalized to the uptake of E. coli bioparticles by DMDMs treated with DMEM alone. Results are shown as the mean (± SEM) of at least 4 independent experiments. Statistical analyses were done by ANOVA, followed by Tukey’s multiple comparison tests; * p < 0.05.