Eosinophil adhesion to human bronchial epithelial cells: regulation by cytokines.
BACKGROUND
Eosinophil infiltration into the airways and interaction with bronchial epithelial cells are important in the pathogenesis of asthma. The purpose of the present study was to elucidate the regulatory mechanisms of eosinophil adhesion to human bronchial epithelial cells.


METHODS
We cultured a human bronchial epithelial cell line, BEAS-2B, on a collagen-coated glass slide. Highly purified human eosinophils were added to each well to allow attachment to epithelium for 30 min. The number of attached eosinophils was counted.


RESULTS
Eosinophil adhesion to epithelial cells was increased when the BEAS-2B cells were pretreated with interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Although IFN-gamma upregulated ICAM-1 expression as shown by flow cytometry, specific neutralizing antibody to ICAM-1 failed to block eosinophil adhesion. Dexamethasone significantly suppressed eosinophil adhesion to bronchial epithelial cells.


CONCLUSIONS
Eosinophil adhesion to bronchial epithelium was dynamically regulated by cytokines, and this process might be a target for therapeutic intervention in the treatment of asthma.
Sato
M
M
Department of Internal Medicine and Physical Therapy, University of Tokyo School of Medicine, Bunkyo-ku, Japan.
Takizawa
H
H
Kohyama
T
T
Ohtoshi
T
T
Takafuji
S
S
Kawasaki
S
S
Tohma
S
S
Ishii
A
A
Shoji
S
S
Ito
K
K
D001249:Asthma / Q000628:therapy; D001980:Bronchi / Q000166:cytology*; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D016207:Cytokines / Q000494:pharmacology*; D004804:Eosinophils / Q000502:physiology*; D004847:Epithelial Cells; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis
D016207:Cytokines; D018799:Intercellular Adhesion Molecule-1