RAW 264.7 cell phagocytosis assay.

RAW 264.7 cells were seeded into a 12-well plate (1 × 10⁷cells/well) and were stimulated with LPS and IFN-γ for 4 h to induce M1 macrophages with or without PZQ pretreatment for 24 h. Then, Alexa Fluor 488-conjugated Escherichia coli (K-12 strain) BioParticles (Invitrogen, USA) were added, and the mixture was incubated in a dark environment for 1 h in serum-free DMEM. The plate was placed in a dark container on ice, with the BioParticle suspension being removed at the end of the incubation. To exclude the surface-bound fluorescence as well as the fluorescence of the cell, trypan blue (1.25 mg/ml) was added for 1 min to quench all of the fluorescence outside the cell. Then, the cells were washed with PBS and the plates were analyzed immediately by using a flow cytometer and a fluorescence microscope.