IL2 and hematopoietic and lymphoid cell neoplasm: Under the IL-2-deficient conditions of tumor microenvironment (TME), our MBP IL-2-expressing NK-92 (MBP NK) cells indeed showed improved proliferation and higher antitumor activity against a hematological tumor model and a solid tumor spheroid model compared to the parental NK-92 cells (Figure 1B and C).