Immunological changes associated with a successful outcome of pollen immunotherapy

Changes in immunological measurements thought to be important in the mechanism of immunotherapy for hay fever were related to objective measurements of treatment outcome. Antigen-specific IgE and IgG, and T suppressor cell status, using monoclonal antibodies and a specific functional assay, were measured before and after immunotherapy. Treatment outcome was assessed using nasal and conjunctival challenge tests. Seventeen subjects received immunotherapy for 6 months. Nine showed a decrease in nasal and/or conjunctival sensitivity, compared with 2 of 13 control subjects (P less than 0.05). Subjects responding to immunotherapy had a significantly higher post treatment IgE level and a higher pre- and post-treatment IgG level than non-responders and controls. Immunotherapy had no effect on suppressor cell status.