The course of allergen-induced leukocyte infiltration in human and experimental asthma.
BACKGROUND
Although the timing of allergen-induced bronchoconstriction is well defined, there is little information about the kinetics of allergen-induced leukocyte infiltration in asthma and its comparability between human and animal models of asthma.


OBJECTIVE
To investigate systematically allergen-induced leukocyte infiltration into the airway lumen in human and experimental asthma by using bronchoalveolar lavage.


METHODS
Patients with allergic asthma were lavaged at different time points as long as 1 week after segmental allergen challenge. Allergen-sensitized mice were lavaged as long as 3 weeks after allergen challenge. Differential cell counts, lymphocyte subsets, and cytokines were assessed in bronchoalveolar lavage fluid.


RESULTS
In both models, neutrophil infiltration was a relatively early event (maximum: 18 hours after challenge). In contrast, eosinophil infiltration peaked 42 hours (human model) to 4 days (mouse model) after allergen challenge, paralleled by an IL-5 peak in this period. There were elevated macrophage counts over a period of several days after allergen challenge in both models. Lymphocytes (predominantly CD4+ T cells) peaked 18 hours after challenge in the human model, but not until 2 weeks after challenge in the murine model.


CONCLUSIONS
Early neutrophil accumulation (within hours after challenge) and delayed eosinophil accumulation (within days after challenge) in the airway lumen are common features of allergen-induced airway inflammation, whereas lymphocyte kinetics are dependent on the asthma model.


CONCLUSIONS
Similarities in the infiltration kinetics of granulocytes after allergen challenge suggest a common role for these cells in asthma, whereas the presumed orchestration of allergic inflammation by lymphocytes appears to differ between the models.
Lommatzsch
Marek
M
Department of Pneumology, Clinic of Internal Medicine, University of Rostock, Ernst-Heydemann-Strasse 6, 18057 Rostock, Germany. marek.lommatzsch@med.uni-rostock.de
Julius
Peter
P
Kuepper
Michael
M
Garn
Holger
H
Bratke
Kai
K
Irmscher
Sabrina
S
Luttmann
Werner
W
Renz
Harald
H
Braun
Armin
A
Virchow
J Christian
JC
D000328:Adult; D000485:Allergens / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002452:Cell Count; D004195:Disease Models, Animal; D004804:Eosinophils / Q000276:immunology*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D015848:Interleukin-5 / Q000032:analysis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D020556:Neutrophil Infiltration
D000485:Allergens; D015848:Interleukin-5; D015847:Interleukin-4; D007371:Interferon-gamma