The benefit of low expression of IL-6 could be partially explained by the study finding that DC-mediated T cell activation was enhanced in IL-6 KO (knock out) mice [61], and the level of serum IL-6 levels in CML-blast crises was higher than that in the chronic phase, and the level in the chronic phase was higher than that in normal controls [62]. This evidence concerns the gene IL6 and chronic myelogenous leukemia, BCR-ABL1 positive.