An evaluation of peripheral blood eosinophil/basophil progenitors following nasal allergen challenge in patients with allergic rhinitis.
OBJECTIVE
To evaluate the effect of a single nasal allergen challenge on peripheral blood eosinophil/basophil (Eo/B) progenitor cells and induced sputum eosinophil counts in subjects with allergic rhinitis.


METHODS
Sixteen adults entered a sequential nasal control and allergen challenge study, outside the pollen season. Blind assessment of peripheral blood Eo/B progenitor colony forming units (CFU), induced sputum and nasal lavage cell counts was made before and 24 h after both challenges. Subjects recorded their rhinitis symptoms and nasal peak inspiratory flow, hourly at home, following both challenges.


RESULTS
When comparing the values 24 h after the control vs. the allergen challenge, there were no significant differences in Eo/B progenitor CFU (control (mean, SD): 3.6 (1.0)/10(6) cells; allergen: 4.4 (1.1)/10(6) cells) or sputum eosinophils (control (median, inter-quartile range): 1.0 (0.3-1.7)%; allergen: 0.7 (0.0-1.3)%) despite a significant increase in the percentage (median (inter-quartile range) of eosinophils in nasal lavage (control: 0.6 (0.1-0.9)%; allergen; 1.9 (0.9-8.1)% and significant worsening of nasal peak inspiratory flow and rhinitis symptoms.


CONCLUSIONS
Despite a significant increase in nasal symptoms and lavage eosinophil counts, a single nasal allergen challenge was not sufficient to elicit a measurable haemopoietic response in circulation, or an increase in sputum eosinophil counts.
Wilson
A M
AM
Airways Research Group, Firestone Institute for Respiratory Health, St Joseph's Healthcare, Hamilton, ON, Canada. a.m.wilson@dundee.ac.uk
Duong
M
M
Crawford
L
L
Denburg
J
J
D000328:Adult; D000485:Allergens; D001249:Asthma / Q000097:blood / Q000150:complications / Q000276:immunology; D001491:Basophils / Q000276:immunology*; D016022:Case-Control Studies; D004804:Eosinophils / Q000276:immunology*; D006801:Humans; D008875:Middle Aged; D009299:Nasal Provocation Tests; D010865:Pilot Projects; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood* / Q000150:complications / Q000276:immunology; D012882:Skin Tests; D013183:Sputum / Q000276:immunology; D013234:Stem Cells / Q000502:physiology*
D000485:Allergens