Immunotherapy with grass pollen major allergens. Immunological results from a prospective 3-year double blind study.

Preseasonal hyposensitization stimulated an intercorrelated increase in both serum-specific IgE and allergen-specific IgG. Subsequent perennial treatment depressed the stimulated IgE response and the basophil cell sensitivity, whereas the allergen-specific IgG response showed further increase and persisted at a high level. Nasal IgE response was stimulated from the second pollen season and subsequently became depressed. One year after the end of hyposensitization the allergen-specific IgG response had fallen by 25-50%.