Expression of total Lyn, p-Lyn, total Btk, and p-Btk was assessed by Western blotting as described in “Western blot experiments.” Score: + indicates positive;±, weak band; and −, negative.

MNC indicates mononuclear cell; SM, systemic mastocytosis; ISM, indolent SM; SSM, smouldering SM; ASM, aggressive SM; MDS, myelodysplastic syndrome; CMML, chronic myelomonocytic leukemia; AML, acute myeloid leukemia; CML, chronic myeloid leukemia; MCL, mast cell leukemia; CNL, chronic neutrophilic leukemia; NBM, normal BM; and nt, not tested.