Myeloperoxidase (MPx): The eosinophils show strong granular staining for MPx, whereas an adjacent neutrophil is negative. Chloroacetate esterase (CAE): Immature neutrophils show positive granular staining reactions, whereas the eosinophils are negative. Alpha-naphthyl butyrate esterase (ANBE): An eosinophilic myelocyte shows weak diffuse cytoplasmic positivity whereas another adjacent eosinophilic myelocyte is negative, as is the lymphocyte. Sudan Black B (SBB): Eosinophil granules are weakly positive (gray) whereas neutrophils are negative. Periodic acid-schiff (PAS): Neutrophils show stronger granular staining for PAS than the eosinophil. The neutrophil myelocyte next to the neutrophil is only weakly positive. Toluidine blue (TB): The eosinophil is negative, whereas the basophil has strong positively stained granules (100x objective for all stains).
