Serum immunologic markers for monitoring allergen-specific immunotherapy.

Allergen immunotherapy is an effective treatment option in patients with IgE-mediated allergy, particularly in those who do not respond to usual antiallergic drugs. Successful immunotherapy has been associated with the suppression of allergic inflammation in target organs and increases in allergen-specific IgG antibodies, particularly the IgG(4) subclass. To date there are no biomarkers that are predictive of the clinical response to immunotherapy. This article explores the possibility that functional assays based on the ability of IgG to compete with IgE and inhibit IgE-allergen complex formation may be surrogate or predictive of the clinical response to immunotherapy.