Fig. 4

ZnPc-EV-mediated PDT induces calreticulin exposure and dendritic cell maturation. MC38 cells were incubated with the ZnPc-EVs for 4 h and left in the dark (dark toxicity, dT), treated with 690 nm light at 200 mW/cm² for 25 J/cm² or subjected to three cycles of freeze-thawing at – 20 °C (FT). After 18 h the cells were stained for viability marker DAPI and DAMP calreticulin (CRT) and analyzed by flow cytometry after live-gating. b D1DCs were treated with 1 or 5 ng/mL poly I:C, or the ZnPc-EVs for 24 h. Cells were then collected, stained with anti-CD86-FITC antibody and measured by flow cytometry. c A co-culture of MC38CFP and D1DCs was subjected to the same treatment as in a, after which the cells were stained with DAPI, anti-CD86-FITC and anti-CD11c-PE. Separation of cell lines was based on gating for CFP+ (cancer cells) or CD11c+ (D1DCs) events after live-gating. Statistical analysis was determined by Students t-test (*P<0.05; mean±SEM; n=3)