IL4 and airway hyperresponsiveness: SA encompasses multiple inflammatory phenotypes, including type 2 (T2) inflammation with elevated IL-4, IL-5, and IL-13 driving eosinophilia, IgE production, and airway hyperresponsiveness (9), as well as non-T2 phenotypes such as neutrophilic airway inflammation, obesity-associated asthma, and paucigranulocytic asthma (10).