In cytochemical staining for peroxidase, which type of cell typically stains negative?

In cytochemical staining for peroxidase, lymphocytes typically stain negative. This result is significant because peroxidase is an enzyme commonly found in granules of certain types of white blood cells. Lymphocytes, which are primarily involved in immune responses and do not have the same granule content as myeloid cells, lack the peroxidase enzyme that would lead to positive staining.

In contrast, neutrophils and eosinophils, which are myeloid cells, contain peroxidase and will stain positive. Basophils also contain peroxidase but are characterized by the presence of heparin and histamine instead and usually exhibit more variability in staining. Monocytes may show weak positivity due to the presence of peroxidase but are not as strongly positive as neutrophils. This makes the negative staining of lymphocytes a distinct and relevant trait when utilizing peroxidase staining to differentiate cell types in hematological analysis.