Cytokine production from sputum cells after allergenic challenge in IgE-mediated asthma.
BACKGROUND
Th2 cytokine production from airway cells is thought to govern the eosinophilic airways inflammation in allergic asthma. Induced sputum has become a widely used technique to assess airways inflammation.


METHODS
By applying the technique of induced sputum to collect airways cells, we have assessed the spontaneous production of a set of cytokines, including interleukin-4, 6, 10, interferon-gamma and tumour necrosis factor-alpha, 6 h after a bronchial allergenic challenge with Dermatophagoides pteronyssinus (Dpt) in 12 sensitized asthmatics and compared the results obtained after inhalation of saline as control. A group of eight healthy non-allergic subjects was enrolled to control for any non-specific effect of Dpt. Cytokines were measured by a dynamic immunoassay during a 24-h sputum cell culture.


RESULTS
Allergen challenge in sensitized asthmatics caused an acute and a late bronchospasm together with a rise in sputum eosinophil counts. Afterwards allergen sputum cells from allergic asthmatics displayed a rise in their production of IL-4 (P < 0.01), IL-6 (P < 0.05) and IL-10 (P < 0.05) when compared to saline. By this time sputum generation of IL-4 in atopic asthmatics was greater than in healthy subjects (P < 0.001). Furthermore, in allergic asthmatics there was a strong correlation between the rise in interleukin-4 production from sputum cells and the rise in sputum eosinophils (r = 0.87, P < 0.001).


CONCLUSIONS
Sputum cell culture is a useful model to assess cytokine production in allergic asthmatics who show a marked up-regulation of Th2 cytokines following acute allergen exposure. The rise in sputum eosinophil count following allergen challenge strongly correlates with the rise in IL-4 generation from sputum cells.
Bettiol
J
J
Dpt of Pneumology and Chronic Inflammatory Disease Research Group, CHU Sart-Tilman, University of Liege, Belgium.
Sele
J
J
Henket
M
M
Louis
E
E
Malaise
M
M
Bartsch
P
P
Louis
R
R
D000328:Adult; D000485:Allergens / Q000008:administration & dosage* / Q000009:adverse effects*; D001249:Asthma / Q000209:etiology* / Q000378:metabolism* / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D001986:Bronchial Spasm / Q000209:etiology / Q000276:immunology / Q000378:metabolism; D016207:Cytokines / Q000096:biosynthesis* / Q000187:drug effects*; D004804:Eosinophils / Q000187:drug effects / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000209:etiology* / Q000378:metabolism* / Q000503:physiopathology; D007958:Leukocyte Count; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D012965:Sodium Chloride / Q000008:administration & dosage / Q000009:adverse effects; D013183:Sputum / Q000166:cytology* / Q000378:metabolism*; D013223:Statistics as Topic; D013997:Time Factors
D000485:Allergens; D016207:Cytokines; D012965:Sodium Chloride