IL33 and chronic myelogenous leukemia, BCR-ABL1 positive: We observed the expression of neutrophil elastase (Fig. 8a, b, Supplementary Fig. 8a, c, d, f) and cathepsin G (Fig. 8a, c, Supplementary Fig. 8b, c, e, f), as well as the mast cell protease, chymase (Fig. 8d, e, Supplementary Fig. 7d, e, g, h), were all significantly increased in the ileum and colon of CML animals, providing a potential explanation for the observed smaller IL-33 cleavage product44.