Human airway submucosal glands augment eosinophil chemotaxis during rhinovirus infection.
BACKGROUND
Asthma exacerbations are frequently associated with rhinovirus (RV) infections. However, the contribution of airway submucosal gland (SMG) to exacerbations of asthma in RV respiratory infection has not been studied.


OBJECTIVE
This study was undertaken to examine whether RV-infected human respiratory SMG cells produce pro-inflammatory cytokines and chemokines for eosinophils, and augment eosinophil transmigration across human airway epithelium.


METHODS
We infected cultured human tracheal SMG cells with RV14, collected culture media at 1, 3, and 5 days after infection, and measured the chemotactic activity for eosinophils in the culture supernatant using a 48-well microchemotaxis chamber and a (51)Cr-labelled eosinophil transmigration assay.


RESULTS
Exposing a confluent human tracheal SMG cell monolayer to RV14 consistently led to infection. Human SMG cells with RV infection secreted soluble factors activating human eosinophil chemotaxis into the culture supernatant in a time-dependent manner, and the culture supernatant significantly augmented the transmigration of (51)Cr-labelled eosinophils through human airway epithelial cell layers from the basal to mucosal side. These effects were completely abolished by a mixture of a monoclonal antibody regulated on activation, normal T cells expressed and secreted (RANTES) and an antibody to granulocyte macrophage-colony stimulating factor (GM-CSF).


CONCLUSIONS
These results suggest that human respiratory SMG cells may augment eosinophil transmigration across the airway epithelium through the secretion of RANTES and GM-CSF after RV infection, and may contribute to exacerbations of asthma.
Furukawa
E
E
Department of Geriatric and Respiratory Medicine, Tohoku University School of Medicine, Sendai, Japan.
Ohrui
T
T
Yamaya
M
M
Suzuki
T
T
Nakasato
H
H
Sasaki
T
T
Kanda
A
A
Yasuda
H
H
Nishimura
H
H
Sasaki
H
H
D000328:Adult; D000368:Aged; D002478:Cells, Cultured; D002631:Chemotactic Factors, Eosinophil / Q000276:immunology; D002634:Chemotaxis, Leukocyte; D003139:Common Cold / Q000276:immunology*; D004702:Endocrine Glands / Q000276:immunology*; D004804:Eosinophils / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D009092:Mucous Membrane / Q000276:immunology; D012229:Rhinovirus; D014132:Trachea / Q000276:immunology*
D002631:Chemotactic Factors, Eosinophil