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

BACKGROUND: The basophil activation test (BAT) reflects the presence of IgE on the cell surface and can be a tool for monitoring the effectiveness of allergen-specific immunotherapy (ASIT). It is likely that spontaneous and allergen-induced BAT levels may change after effective subcutaneous immunotherapy (SCIT) and this is of clinical importance. AIMS: determination of basophil activation markers in patients sensitized to weed pollen during SCIT. MATERIALS AND METHODS: A real clinical study (2 years, 60 patients) with allergic rhinitis who underwent SCIT with weed allergens for 2 seasons. The proportion of basophils expressing CD203c spontaneously and after exposure to a trigger allergen was determined. BAT was performed before treatment, after the first and second courses of pre-season SCIT (0, 3, 15 months of treatment). The effectiveness of SCIT was assessed by the dynamics of the symptom scale (Rhinoconjunctivitis total symptom score) and the drug assessment (Daily medical score). RESULTS: SCIT with water-salt extracts was effective: 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), DMS score from 2.0 [2.0; 2.0] vs 1.0 [1.0; 2.0] points (p0.001). Spontaneous BAT remained unchanged after the first course of ASIT. Mean BAT values ​​before therapy and after the first course of SCIT did not differ (8.15 [6.10; 11.9] vs 9.0 [6.30; 12.0] %). After the second course of treatment, spontaneous BAT decreased (8.15 [6.10; 11.9] vs 6.20 [4.27; 9.00] %, 2 = 15.5, p0.001). Allergen-induced BAT decreased significantly from the first year of treatment. The overall change in the total group for BAT with ragweed after the first course of SCIT was 11.25 (CI 95 %: 7.10; 15.10) %, p 0.001. The overall difference in the induced ВAT test at the end of therapy reached 8.63 (CI 95: 5.30; 12.05) %, p 0.001. After the first course of therapy with mugwort allergens, the indices of induced BAT decreased by 12.0 (CI 95 %: 6.95; 17.90) %, p 0.001; after the second course, the difference from the initial values ​​was 9.67 (CI 95%: -6.85; 15.90) %, p0.001. CONCLUSIONS: SCIT with ragweed and mugwort allergens was effective. The change in spontaneous and induced BAT is associated with a positive effect of ASIT.