GZMB and neoplasm: A significant difference between Plasmodium immunotherapy and checkpoint blockade therapy is that, the former promotes CD8+ T cells to express and secrete perforin and granzyme B, but not express and secrete IFN-γ within tumor [21], even though a lot of IFN-γ are produced in peripheral blood and spleen of Plasmodium infected tumor-bearing mice [19], therefore reduces the level of IFN-γ within tumor [21].