Here, rIL-33 treatment reduced pulmonary and liver metastases by CT26 cells when injected via the tail vein and into the splenic capsule respectively, and concomitant anti-CD40L treatment significantly promoted tumour burden and reduced IFNγ expression in CD4+ T cells, NK cells and CD8+ T cells in IL-33 treated mice. The gene discussed is IL33; the disease is neoplasm.