Whereas a blockade of AMCase by allosamidin or an anti-AMCase antibody ameliorated airway inflammation and hyper-responsiveness in a non-chitin-dependent allergy model,8 the opposite observation was made in a chitin-dependent model of pulmonary inflammation.42 This points to the detrimental role of a misguided and overshooting immune response in the absence of chitinous pathogens. This evidence concerns the gene CHIA and allergic disease.