Therapeutic and prophylactic deletion of IL-4Ra-signaling ameliorates established ovalbumin induced allergic asthma.

BACKGROUND

Allergic asthma is a chronic inflammatory airway disease driven predominantly by a TH 2 immune response to environmental allergens. IL-4Rα-signaling is essential for driving TH 2-type immunity to allergens. Anti-TH 2 therapies have the potential to effectively reduce airway obstruction and inflammation in allergic asthma.

OBJECTIVE

We investigated potential therapeutic effects of selective inhibition of this pathway in mice with established allergic airway disease. We further investigated whether IL-4Rα disruption in systemically sensitized mice can prevent the onset of the disease.

METHODS

We used RosacreERT2 IL-4Rα-/lox mice, a tamoxifen (TAM)-inducible IL-4Rα knockdown model to investigate the role of IL-4/IL-13 signaling prior to the onset of the disease and during the effector phase in the ovalbumin-induced allergic airway disease.

RESULTS

Inducible deletion of IL-4Rα demonstrated therapeutic effects, on established allergic airway disease, and prevented the development of ovalbumin-induced airway hyperreactivity, eosinophilia, and goblet cell metaplasia in allergen-sensitized mice. Interestingly, IL-4Rα knockdown after allergic sensitization did not induce TH 17, a neutrophilic inflammatory response as observed in global IL-4Rα-deficient mice after intranasal allergen challenge.

CONCLUSION

Abrogation of IL-4Rα signaling after allergic sensitization would have significant therapeutic benefit for TH 2-type allergic asthma.