Polymersomes uptake
Peritoneal macrophages from heterozygous RosaTdTomato female mice were seeded at the density of 105 cells/well on 8 microwell glass-bottom petri dishes (ibidi). After 24 h, cells were treated for 3 h as specified and then incubated with Cy5-labelled nanoparticles for 1 and 3 hours. After medium discharge, cells were washed 3 times in PBS to remove any excess of nanoparticles and fixed in formaldehyde (4%) for 10 minutes, then washed and analysed by confocal microscopy (ZEISS Axio Observer). Fluorescence intensity of polymersomes inside macrophages was scored by ImageJ. The number of polymersomes-positive cells was counted in 4 fields/well, with an average of 200 total cells counted in each well.