BACKGROUND: Allergic rhinitis is characterized by the epithelial accumulation of 
cells, particularly mast cells and eosinophils. There is little information 
relating to the chemotaxins responsible for mast cell epithelial accumulation in 
this disease.
OBJECTIVE: Expression of the mast cell chemoattractants TGF-beta, eotaxin, and 
stem cell factor and their receptors was investigated in tissue sections from 
biopsy specimens obtained from patients with naturally occurring allergic 
rhinitis.
METHODS: Specific immunohistochemical staining was performed on thin sections of 
inferior turbinate biopsy specimens from patients with perennial and seasonal 
allergic rhinitis and, for comparison, from nonatopic and, where relevant, 
atopic healthy volunteers without rhinitis. Sequential staining of adjacent 
2-microm sections was undertaken to colocalize TGF-beta receptors to mast cells.
RESULTS: Evidence was found of significantly increased epithelial 
immunoreactivity for TGF-beta1, TGF-beta2, TGF-beta3, TGF-beta receptor I, 
TGF-beta receptor II, and TGF-beta receptor III in patients with perennial and 
seasonal allergic rhinitis compared with that seen in healthy control subjects. 
TGF-beta receptors I and II were found to colocalize to mast cells. Eotaxin 
epithelial immunoreactivity was significantly increased in the perennial group, 
although there were no corresponding disease-related differences found in 
relation to CCR-3 immunoreactivity at this site. There was no increase in stem 
cell factor immunoreactivity within the epithelium in naturally occurring 
disease. Significant correlations were found between epithelial immunoreactivity 
for TGF-beta1, TGF-beta2, TGF-beta receptor I, TGF-beta receptor II, and the 
number of epithelial mast cells.
CONCLUSION: These findings of enhanced epithelial TGF-beta immunoreactivity in 
patients with rhinitis, the correlation with intraepithelial mast cell numbers, 
and the colocalization of TGF-beta receptors to mast cells suggest that the 
epithelial expression of TGF-beta might represent an important biologic process 
involved in either the recruitment or retention of mast cells within the 
epithelium in naturally occurring allergic rhinitis.