Endogenous IL-18 in experimentally induced asthma affects cytokine serum levels but is irrelevant for clinical symptoms.
T cells and T cell derived cytokines are involved in the complex pathogenesis of asthma. The role of the cytokine IL-18 however, is not clearly defined so far. On the one hand side IL-18 induces Th1-type cytokines and thereby might counter-regulate Th2-mediated allergic asthma. On the other hand IL-18 also bears pro-inflammatory effects possibly enhancing experimental asthma. In order to elucidate the role of IL-18 in allergic pulmonary inflammation typical symptoms were compared after induction of experimental asthma in IL-18(-/-) and in wild type mice. Asthma was induced using ovalbumin (OVA) as allergen for sensitization and challenge. Sham sensitized and OVA challenged mice served as controls. Bronchoalveolar lavage-fluid cytology, leukocyte infiltration in lung tissues, serum levels of OVA-specific IgE and cytokines, and lung function were analyzed. Clear differences could be observed between control and asthmatic mice, both in wild type and IL-18(-/-) animals. Surprisingly, no differences were found between asthmatic wild type and IL-18(-/-) mice. Thus, in contrast to conflicting data in the literature IL-18 did not suppress or enhance the pulmonary allergic immune response in a murine experimental model of asthma.
Hartwig
Christina
C
Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany.
Tschernig
Thomas
T
Mazzega
Miriam
M
Braun
Armin
A
Neumann
Detlef
D
D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000473:pathology; D001985:Bronchial Provocation Tests; D001992:Bronchoalveolar Lavage Fluid; D004195:Disease Models, Animal; D004804:Eosinophils / Q000276:immunology; D005260:Female; D007114:Immunization; D007073:Immunoglobulin E / Q000097:blood; D020381:Interleukin-17 / Q000097:blood; D020382:Interleukin-18 / Q000097:blood*; D015848:Interleukin-5 / Q000097:blood; D007958:Leukocyte Count; D008168:Lung / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000494:pharmacology; D010993:Plethysmography, Whole Body
D020381:Interleukin-17; D020382:Interleukin-18; D015848:Interleukin-5; D007073:Immunoglobulin E; D010047:Ovalbumin