Differences between cytokine release from bronchial epithelial cells of asthmatic patients and non-asthmatic subjects: effect of exposure to diesel exhaust particles.
BACKGROUND
Recent evidence suggests that the airways of asthmatics are more susceptible to adverse effects of air pollutants than the airways of non-asthmatics, but the underlying mechanisms are not clear.


METHODS
We have cultured bronchial epithelial cells (HBEC) from biopsies of atopic mild asthmatic patients and non-atopic non-asthmatic subjects, and investigated constitutive and diesel exhaust particles (DEP)-induced release of several pro-inflammatory mediators.


RESULTS
HBEC of asthmatic patients constitutively released significantly greater amounts of IL-8, GM-CSF and sICAM-1 than HBEC of non-asthmatic subjects. RANTES was only released by HBEC of asthmatic patients. Incubation of the asthmatic cultures with 10 micrograms/ml DEP significantly increased the release of IL-8, GM-CSF and sICAM-1 after 24 h. In contrast, only the higher concentrations of 50-100 micrograms/ml DEP significantly increased the release of IL-8 and GM-CSF from HBEC of non-asthmatics.


CONCLUSIONS
These results suggest that the increased sensitivity of the airways of asthmatics to air pollutants such as DEP may, at least in part, be a consequence of greater constitutive and pollutant-induced release of specific pro-inflammatory mediators from their bronchial epithelial cells.
Devalia
J L
JL
Academic Department of Respiratory Medicine, St. Bartholomew's and The Royal London School of Medicine and Dentistry, London Chest Hospital, London, UK.
Bayram
H
H
Abdelaziz
M M
MM
Sapsford
R J
RJ
Davies
R J
RJ
D000328:Adult; D000485:Allergens / Q000276:immunology; D001249:Asthma / Q000276:immunology* / Q000473:pathology; D001980:Bronchi / Q000276:immunology* / Q000473:pathology; D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology* / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D001335:Vehicle Emissions / Q000009:adverse effects
D000485:Allergens; D016207:Cytokines; D001335:Vehicle Emissions