Intranasal challenge with increasing ovalbumin doses differently affects airway hyperresponsiveness and inflammatory cell accumulation in mouse model of asthma.
OBJECTIVE
To investigate whether challenge with increasing allergen doses could differently affect allergen-induced airway hyperresponsiveness (AHR) and inflammatory cell accumulation in mouse model of asthma, providing an experimental model to investigate their relationship.


METHODS
AHR and accumulation of inflammatory cells in bronchoalveolar lavage fluid (BALF) and into the lungs were compared in ovalbumin-sensitized mice that were challenged intranasally with 2.5, 10, 25 or 100 microg of ovalbumin/mouse.


RESULTS
Both AHR and inflammatory cell accumulation were proportional to the ovalbumin dose used for challenge. However, in group challenged with 10 microg of ovalbumin airway inflammation was present, although allergen-induced AHR was not detected. Additional analysis indicated that neither mucous hyperproduction nor eosinophil degranulation could be correlated to presence of AHR in this model, whereas concentration of interleukin (IL)-13 in BALF was increased only in those groups in which AHR was present.


CONCLUSIONS
Altogether, intranasal challenge of mice with increasing allergen doses could serve as a suitable experimental system for investigation of mechanisms by which airway inflammation leads to allergen-induced AHR. Our initial findings are in line with previous reports that dissociate AHR from amount of eosinophil accumulation and imply the role of IL-13 in this process.
GlaxoSmithKline Research Centre Zagreb Limited, Zagreb, Croatia. berislav.bosnjak@meduniwien.ac.at
Berislav
B
Bosnjak
Vanesa
V
Ivetić Tkalcević
Koraljka
K
Durić
Daniela
D
Belamarić
Snjezana
S
Cuzić
Zeljko
Z
Ferencić
Karmen
K
Brajsa
Ines
I
Glojnarić
Roberto
R
Antolović
Boska
B
Hrvacić
D000281:Administration, Intranasal; D000818:Animals; D001249:Asthma / Q000276:immunology*; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000276:immunology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D016207:Cytokines / Q000276:immunology; D004195:Disease Models, Animal; D047209:Eosinophil Peroxidase / Q000378:metabolism; D004804:Eosinophils / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D018793:Interleukin-13 / Q000276:immunology; D008168:Lung / Q000166:cytology / Q000276:immunology / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology
D016207:Cytokines; D018793:Interleukin-13; D010047:Ovalbumin; D047209:Eosinophil Peroxidase