Characterization of mast cell populations using different methods for their identification.

Mast cells are ubiquitous throughout the human tissues and play an essential role in physiology and pathology. For evaluation of patients with pathological conditions, mast cells were primarily detected using metachromatic staining with toluidine blue. In the last decades, the staining arsenal of pathologists was enriched with enzyme histochemical and immunohistochemical methods, and it was established that depending on species and tissue localization mast cells are not similar both in appearance and function. The aim of this study was to characterize different mast cell populations using the up-to-date methods of their identification. We compared standard metachromatic method for mast cells with enzyme histochemical detection of chloroacetyl esterase and with immunohistochemical detection of tryptase and chymase in human and rodent tissues. Combination of these methods allowed us to assay quantitatively mast cell populations in different organs of humans and rodents. Furthermore, we assessed the appropriate implementation of each of these methods for mast cell identification in diagnostic labs.