Fig. 4

Intracellular transport and distribution of the nanoparticles. EEA1: The co-locations (yellow) of EEA1 (red) and 30 nm Ps particles (green) were present at 10 min, the yellow spots were magnified at right and left superior corners. The co-locations decreased at 30 min, there was hardly co-location and the LVLS generated at 50 min. Rab7: Rab7 co-located hardly with 30 nm Ps particles at 10 min, 30 min and 50 min, the LVLS were also present in the cell at 50 min. LAMP-1: LAMP-1 didn’t co-locate with 30 nm Ps particles from 10 min to 50 min. The co-locations of EEA1 and 30 nm Ps particles at 10 min indicated that the particles entered the cell by endocytic transport. Following that, the particles didn’t co-locate with Rab7 and LAMP-1. That indicated that the particles were not transported through late endosome to lysosome. It meant that the 30 nm Ps particles induced the LVLS formation in early endosome