Suppression spontaneous and induced expression of CD203c basophils after subcutaneous immunotherapy with ragweed and mugwort allergens

Abstract

BACKGROUND: The basophil activation test (BAT) reflects the presence of immunoglobulin E on the cell surface and can be a tool for monitoring the effectiveness of allergen-specific immunotherapy. Spontaneous and allergen-induced BAT levels may likely change after effective subcutaneous immunotherapy, and this is of clinical importance. AIMS: To determine the basophil activation markers in patients sensitized to weed pollen during subcutaneous immunotherapy MATERIALS AND METHODS: This clinical study of 2 years included 60 patients with allergic rhinitis who underwent subcutaneous immunotherapy with weed allergens for two seasons. The proportion of basophil-expressing CD203c, spontaneously and after exposure to a trigger allergen, was determined. BAT was performed before treatment and after the first and second courses of preseason subcutaneous immunotherapy (0, 3, and 15 months of treatment). The effectiveness of subcutaneous immunotherapy was assessed by the dynamics of the symptom scale (Rhinoconjunctivitis total symptom score [RTSS]) and the drug assessment (Daily medical score [DMS]). RESULTS: Subcutaneous immunotherapy with watersalt extracts was effective. The median RTSS in patients after two courses decreased from 13.0 [10.0; 15.0] to 4.5 [3.00; 7.25] points (p 0.001) and DMS score from 2.0 [2.0; 2.0] to 1.0 [1.0; 2.0] points (p 0.001). Spontaneous BAT remained unchanged after the first course of allergen-specific immunotherapy. The mean BAT values before therapy and after the first course of subcutaneous immunotherapy did not differ (8.15% [6.10; 11.9] vs. 9.0% [6.30; 12.0]). The spontaneous BAT decreased after the second course of treatment (8.15% [6.10; 11.9] vs. 6.20% [4.27; 9.00], 2=15.5, p 0.001). Allergen-induced BAT significantly decreased from the first year of treatment. The overall change in the total group for BAT with ragweed after the first course of subcutaneous immunotherapy was 11.25% (95% confidence interval [CI]: 7.1015.10, p 0.001). The overall difference in the induced ВAT test at the end of therapy reached 8.63% (95% CI: 5.3012.05, p 0.001). The indices of induced BAT decreased by 12.0% after the first course of therapy with mugwort allergens (95% CI: 6.9517.90, p 0.001), and the difference from the initial values after the second course was 9.67% (95% CI: 6.8515.90, p 0.001). CONCLUSIONS: Subcutaneous immunotherapy with ragweed and mugwort allergens was effective. The change in spontaneous and induced BAT is associated with a positive effect of allergen-specific immunotherapy.