Control liposome

Clodronate liposome and control liposome were purchased from FormuMax Scientific Inc. (Sunnyvale, CA, USA). 10 μl/kg of clodronate containing liposome (CL) or empty liposome (EL) was intraperitoneally injected 4 days before first CS exposure and 5 μl/kg of CL or EL was given by i.p. injection every 4 days during experiment for longer macrophage depletion. The injected doses and intervals of Clodronate liposome and control liposome were determined by following the protocol of FormuMax Scientific Inc. (Sunnyvale, CA, USA).

All human PDAC tissues were obtained from Ruijin Hospital, Shanghai Jiao Tong University School of Medicine. The protocols using human specimens were approved by the Ethics Committee of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine (ID: 2021-194).
For the studies involving animals, appropriate permission was given from the Animal Experimental Ethical Inspection of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine (20180509). A sample of 6-week-old female C57BL/6 mice were injected subcutaneously with 5 × 10⁵ Panc02 cells or 3 × 10⁵ KPC cells (mouse pancreatic cancer cell lines) on day 0. For macrophage-depletion studies, mice were intraperitoneally injected with clodronate liposomes or control liposomes (FormuMax Scientific, Sunnyvale, CA, USA) at 200 μL per mouse on days -1 and 0, and every 3 days afterward until the completion of the study. In the T-cell-depletion experiment, an antibody (Ab) to deplete CD8⁺ cells (clone YTS 169.4; BioXCell) was injected intraperitoneally at 200 µg per mouse on days -1 and 0, and every 5 days afterward until the end of the study. The tumor volume was calculated as width² × length/2. On day 20, all mice were sacrificed, and tumor tissues were collected for further analysis.