Fig. 1

Anti-HER2 CAR-Ms specifically target HER2-positive cancer cells. A A diagram of the anti-HER2-CAR construct. B Overview of primary macrophage differentiation from bone marrow and the lentivirus transduction protocol. C Representative flow cytometry analysis of the CAR transduction frequency in lentivirus-transduced primary macrophages after 72 h. D Representative flow cytometry analysis of CAR expression on macrophages after lentivirus transduction, with recombinant HER2 protein binding and staining with an APC-conjugated anti-His tag antibody. E–F Representative flow cytometry analysis of HER2 expression in sorted cells of the murine tumor cell lines MC38 (E) and B16F10 (F) after stable transduction with the truncated HER2 lentivirus. G Flow cytometry-based phagocytosis of mCherry⁺ MC38-wild type or mCherry⁺ MC38-HER2 target cells by anti-HER2 CAR-Ms at an E:T = 5:1 ratio. The double-positive cell population represents the target cells engulfed by macrophages. H Luciferase-based killing assay of Luc⁺ MC38-wild type or Luc⁺ MC38-HER2 target cells by anti-HER2 CAR-Ms at an E:T = 5:1 ratio in vitro. ***, p < 0.001