Clinical and immunologic changes after allergen immunotherapy with Hop Japanese pollen.

Abstract

BACKGROUND AND OBJECTIVE: Hop Japanese (Hop J) pollen has been reported as one of the major causative pollen allergens in the autumn season. There have been no published data regarding the clinical and immunologic effects of Hop J pollen immunotherapy in sensitized patients. In this study, we evaluated clinical and immunologic effects of Hop J immunotherapy.

PATIENTS AND METHODS: Pollens were collected in our area, and "Depo-Hop J" was prepared in the laboratory of Allergopharma (Reinbek, Germany). Fifteen asthmatic patients who had Hop J immunotherapy for > 1 year were enrolled. Their clinical parameters, such as asthma symptom scores, were monitored. Skin reactivity to Hop J and degree of airway hyperresponsiveness to methacholine were measured before and 1 year after the immunotherapy. Sera were collected before the immunotherapy, at the end of initial therapy, and 1 year after the therapy. Serum total IgE levels were compared by radioimmunoassay. Serum-specific IgE, IgG1, and IgG4 levels to Hop J were compared by ELISA. To evaluate the changes of cellular mechanisms, soluble CD30 (sCD30), soluble interleukin (IL)-2 receptor (sIL-2R), soluble CD23 (sCD23), and IL-10 levels were measured by ELISA.

RESULTS: Specific IgG1 and IgG4 levels began to increase at the end of the initial therapy (P < 0.05) with significant decreases in symptom scores (P < 0.05), whereas total and specific IgE levels showed variable responses during the immunotherapy with no statistical significance (P > 0.05). Serum sIL-2R and sCD30 levels decreased significantly (P < 0.05) 1 year after immunotherapy. No significant changes were noted in sCD23, IL-10, skin reactivity to Hop J, or airway responsiveness to methacholine (P > 0.05).

CONCLUSIONS: We are certain that Hop J allergen immunotherapy, if carried out properly according to suitable indications, can favorably influence asthma. Thus, an increase in specific IgG4 and IgG1 antibodies and reduction of a possible Th2 lymphocyte marker (sCD30) may be associated with symptomatic improvements.