The separate analysis of induced sputum from three consecutive sampling periods of a single induction procedure demonstrated significant changes in their cellular and biochemical composition, both in healthy and mild asthmatic subjects.

These results demonstrate, that increased reactivity to histamine and airway contraction to allergen induced by passive sensitization, occur through independent mechanisms and that, unlike allergen-sensitivity, histamine hypersensitivity is caused by a serum factor other than IgE.

No abstract