TNF and leukemia: Recently, it has been reported that inflammatory factors TNF-α and TFN-γ can promote MSCs to produce a large amount of PD-L1 and PD-L2, which bind to the PL-1 of T cells and inhibit the activation of T cells to promote immune escape (Davies et al., 2017), but it has not yet begun to use the immune checkpoint blockade in leukemia.