Induction of apoptosis in bronchial eosinophils: beneficial or harmful?
BACKGROUND
Prominent eosinophil infiltration takes place in asthmatic bronchi, and damages bronchial epithelial cells.


OBJECTIVE
This study was designed to investigate whether induction of apoptosis in infiltrated cells in the airways is beneficial or harmful.


METHODS
A/J mice, which are genetically predisposed to be hyperresponsive to acetylcholine, were immunized with ovalbumin (OA) and alum. Thereafter, they were subjected to a 2-week regimen of OA inhalation, during which they were also administered either hamster anti-mouse Fas monoclonal antibody or hamster IgG (sham control) intranasally. Pulmonary function was then analyzed using whole-body plethysmography.


RESULTS
Inhalation of OA increased both airway responsiveness to acetylcholine and infiltration of eosinophils. Administration of anti-Fas antibody induced apoptosis in the infiltrating eosinophils and abolished the increase in airway responsiveness to acetylcholine.


CONCLUSIONS
Induction of apoptosis in eosinophils infiltrating asthmatic bronchi has a beneficial effect on airway hyperresponsiveness.
Yamashita
N
N
Department of Medicine, Teikyo University School of Medicine, Tokyo, Japan.
Tajima
M
M
Nakano
J
J
Arioka
H
H
Arai
H
H
Miyasaka
T
T
Kubota
S
S
Kawashima
R
R
Ohta
K
K
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D017209:Apoptosis; D001980:Bronchi / Q000187:drug effects / Q000473:pathology*; D016535:Bronchial Hyperreactivity / Q000517:prevention & control*; D006224:Cricetinae; D004804:Eosinophils / Q000502:physiology*; D051379:Mice; D010047:Ovalbumin / Q000276:immunology; D019014:fas Receptor / Q000502:physiology
D000911:Antibodies, Monoclonal; D019014:fas Receptor; D010047:Ovalbumin; D000109:Acetylcholine