Fig. 3
HPCs take up more apoHPC-MPs than apoLTC-MPs or apoHep-MPs. A, B WB-F344 cell (5 × 103) were labeled with GFP (green fluorescence), incubated for 30 min with 1 × 105 apoHPC-MPs, apoLTC-MPs or apoHep-MPs containing DOX (red fluorescence). The uptake of MPs into WB-F344 cells was observed by fluorescence microscopy. Representative images are shown in A. The percentage of WB-F344 cells with red fluorescence (indicating uptake of MPs) was calculated in each group. The combined data from three experiments are shown in B. Data are presented as mean ± SD. **p < 0.01, ***p < 0.001. C, D 1 × 106 ApoHPC-MPs, apoLTC-MPs and apoHep-MPs containing doxorubicin (red fluorescence) were incubated with WB-F344 cells (3 × 105) for 30 min. The percentage of WB-F344 cells containing red fluorescence was measured by flow cytometry. Representative flow cytometry data are shown in C. The combined data from three experiments are shown in (D). Data are presented as mean ± SD. **p < 0.01. E Liver organoids were cultured in vitro. 1 × 104 apoHPC-MPs, apoLTC-MPs or apoHep-MPs were incubated with liver organoids for 30 min. The uptake of MPs into organoids was observed by fluorescence microscopy. Representative images are shown. Nuclei were stained with DAPI (blue). F 1 × 107 apoHPC-MPs, apoHep-MPs or apoLTC-MPs were intrasplenically injected into DEN-treated rats. 30 min after injection, liver slices were acquired for fluorescence detection. HPCs were recognized by antibodies against CK19 (green). Nuclei were stained with DAPI (blue). HPCs efficiently took up red fluorescent apoHPC-MPs. G WB-F344 cells (3 × 105) were incubated with apoHPC-MPs (1 × 105) for 30 min. Then WB-F344 cells were treated with 0.2 × trypsin/EDTA buffer for 1 min and then washed with citric acid buffer several times to remove all non-internalized apoHPC-MPs bound to the surface of WB-F344 cells. Nuclei were stained with DAPI (blue). H 3 × 105 WB-F344 cells were incubated with 2 × 105 apoHPC-MPs for 0.5, 2, and 4 h. After washing, the samples were subjected to flow cytometric analysis. A representative image is shown here