Effect of topical corticosteroids on seasonal increases in epithelial eosinophils and mast cells in allergic rhinitis: a comparison of nasal brush and biopsy methods.
BACKGROUND
Nasal brushing and nasal biopsy are well-tolerated sampling techniques. Seasonal grass pollen-induced rhinitis is characterized by epithelial mast cell infiltration and seasonal increases in both epithelial and sub-mucosal eosinophils.


OBJECTIVE
To compare the ability of the nasal brush and nasal biopsy techniques to detect natural seasonal increases in eosinophils and mast cells, and to assess the influence of topical corticosteroid.


METHODS
Nasal brush samples and nasal biopsies were collected from 46 grass pollen-sensitive seasonal rhinitis patients before the grass pollen season and at the peak of the pollen season following 6 weeks' treatment with either fluticasone propionate aqueous nasal spray (200 microg, twice daily) or placebo nasal spray.


RESULTS
Placebo patients showed seasonal increases in epithelial eosinophils both with nasal brushing (P < 0.0001) and biopsy (P < 0.001). Epithelial mast cell numbers also increased during the pollen season as detectable by brushing (P < 0.0001) and biopsy (P < 0.03). Changes in cell numbers measured by nasal brushing correlated with those observed with nasal biopsy, both for eosinophils and mast cells (P < 0.05). Sub-mucosal eosinophils but not mast cells also increased during the pollen season (P < 0.002). Nasal brushing and biopsy revealed that fluticasone treatment inhibited seasonal increases in epithelial eosinophils (P < 0.00001) and epithelial infiltration by mast cells (nasal brushing P < 0.00001 and nasal biopsy P < 0.01). Fluticasone also inhibited seasonal increases in sub-mucosal eosinophils (P < 0.001) and significantly reduced nasal symptoms (P < 0.001).


CONCLUSIONS
Nasal brushing harvests sufficient inflammatory cells from the surface of the nasal mucosa to be used in lieu of nasal biopsies in observation of the effect of drugs on the nasal epithelium.
Jacobson
M R
MR
Upper Respiratory Medicine, Imperial College School of Medicine at the National Heart and Lung Institute, London, UK.
Juliusson
S
S
Löwhagen
O
O
Balder
B
B
Kay
A B
AB
Durham
S R
SR
D000287:Administration, Topical; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D001706:Biopsy / Q000379:methods; D004804:Eosinophils / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008407:Mast Cells / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D009297:Nasal Mucosa / Q000187:drug effects / Q000276:immunology / Q000473:pathology*; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis / Q000188:drug therapy*; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones