CSF2 and neoplasm: Tumor tissues were extracted and immune cell infiltration in tumor tissues was detected by HE staining and the IHC method.<h4>Results</h4>The recombinant plasmids carrying PD-1v, IL-2/15, IL-12, and GM-CSF were successfully constructed, and the Western blot and ELISA results showed that PD-1v, IL-12, and GM-CSF were expressed in the supernatant of CT26 cells 48 h after in vitro cell transfection.