Immunophenotypic profile of BMMC from healthy subjects vs. SM patients classified according to the distinct diagnostic and prognostic categories of the disease. Results are expressed as stain index (SI, difference in signal width between the positive and the negative population divided by the signal spread of the negative population) for the CD22-APC (panel A), CD25-PE (panel B), CD30-PE (panel C), CD33-APC (panel D), CD123-APC (panel E) and FCεRI-FITC (panel F) markers. The SI threshold for positivity was set at ≥1.5 and is represented by horizontal dotted lines. p-values < 0.05 were considered to be associated with statistical significance (thin dotted lines). Mann Whitney-U test was used for comparisons between continuous variables (SI values) from normal/reactive individuals vs. SM patients or among the different subtypes of SM (SPSS 23 software, IBM, Armonk, NY, USA).