An increased number of mast cells and eosinophils can be recognized in the epithelial layer of nasal mucosa from allergic subjects; these cells are known to play an important role in the manifestation of nasal
allergy. Eosinophils accumulate under the effect of eosinophil
chemotactic factor released by mast cells. However, the mechanism of accumulation of mast cells has not yet been clarified. Our previous studies have shown that colony stimulating activity of the basophil/eosinophil lineage is enhanced under proliferative conditions for nasal epithelial cells. We therefore studied the distribution of mast cells and eosinophils in
inverted papilloma of the nose, in which we can identify proliferation of nasal epithelial cells. Nasal
inverted papilloma from 5 patients were examined for mast cell and eosinophil distributions. Serial staining of nasal
inverted papilloma showed that the number of mast cells and the percentage of
formalin sensitive mast cells within 50 microns of the
tumor site and 50 microns above the basement membrane were 16576 +/- 5729/mm3 (90.8%) and 4697 +/- 304/mm3 (76.1%), respectively. However, in comparison with the
tumor site, significant differences in the distribution and number of mast cells were seen in the stromal area. The number of mast cells and the percentage of
formalin sensitive mast cells within 50 microns and 50 microns above the basement membrane were 2880 +/- 238/mm3 (0%) and 3096 +/- 152/mm3 (0%), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)