Different patterns of antigen-induced histamine release during immunotherapy in insect venom and pollen allergy.

Antigen-induced histamine release from whole blood was shown to be a suitable parameter for the diagnosis of hypersensitivity in both patients allergic to bee or wasp venom as well as in patients suffering from seasonal tree pollen allergy. Although both groups were treated successfully by specific immunotherapy, only in patients with insect allergy venom induced histamine release decreased significantly during therapy, whereas, in the patient with pollinosis, pollen induced histamine release did not change significantly during or after treatment. This discrepancy in the antigen-induced histamine release could either be due to different routes of immunization with the allergen and/or is caused by the atopic status which is prevalent in patients with pollinosis but not in insect allergic subjects.