Inhibiting intracellular CD28 in cancer cells enhances antitumor immunity and overcomes anti- PD-1 resistance via targeting PD-L1

In vivo genome-wide CRISPR screening unraveled the non-classical role of cancer cell Cd28 in tumor immune escape, and identified cancer cell Cd28 as a novel target in breast cancer immunotherapy by modulating tumor immunogenicity and anti-tumor CD8+ T cell responses. Overall design: 4T1 cells infected by mGeCKO library lentivirus were orthotopically inoculated into Six-to-ten-week-old female BALB/c. Single-cell RNA seqencing (Chromium, 10X Genomics) was performed to compare the tumor-infiltrting immune cells (sorted by Fluorescence-activated cell sorting) between sgNC and sgRNA infected tumors on day 6, 8, 10 after tumor implantation.