In Vitro Evaluation of the Biological Responses of Canine Macrophages Challenged with PLGA Nanoparticles Containing Monophosphoryl Lipid A
Fig 5
Transmission electron microscopy (TEM) evaluation of cellular uptake of PLGA NP preparations by canine macrophages.
Day 7 canine macrophages cultures (1x106) were incubated with 50 μg/mL of PLGA/OVA/MPLA NPs. After 24 hours, nonadherent cells were harvested and analyzed by TEM. The macrophages without treatment (A) and (B) contain empty phagocytic vacuoles while the macrophages incubated with PLGA NP/OVA/MPLA (C) and (D) demonstrated absence of vacuoles and the presence of electron-dense material reflecting uptake of the NPs. (A) scale bar = 2 μm, (B) and (C) scale bar = 1 μm, and (D) scale bar = 500 nm. Similar data were obtained in three independent experiments.