[Differentiation and proliferation of mast cells in nasal mucosa]

We determined the distribution of mast cells in nasal mucosa and studied their proliferation. Inferior turbinate mucosa was sampled in 13 patients with allergic rhinitis (allergic group) and 5 without (non allergic group) and stained immunohistochemically using anti mast cell tryptase antibody, anti-c-kit antibody, anti-PCNA antibody, and anti mast cell chymase antibody. Tissue sections stained with anti tryptase antibody revealed a higher degree of infiltration of tryptase-positive cells, i.e., mast cells, in the allergic group than in non allergic group. In the allergic group, the number of tryptase-positive cells, c-kit-positive cells, and PCNA-positive cells was significantly greater in the epithelium and shallow lamina propria than that in the deep lamina propria. Tryptase-positive, c-kit-positive cells, i.e., c-kit-positive mast cells, and tryptase-positive, PCNA-positive cells, i.e., PCNA-positive mast cells, were also abundunt in the epithelium and shallow lamina propria. The stem cell factor and c-kit receptor are reported to play a primary role in mast cell differentiation and proliferation. PCNA-positive cells represent actively proliferating cells. Based on the above, we concluded that mast cells in the epithelium and shallow lamina propria in the allergic group differentiated and proliferated more actively than those in the deep lamina propria.