The Usefulness of CD203c Expression Measurement on Basophils after Activation with Grass Pollen and Dermatophagoides pteronyssinus Antigens. Preliminary Study

Introduction: 'Gold standard' in the diagnosis of atopic disease are skin prick tests and specific IgE evaluation. Well-established in vitro tests, such as the histamine release test, the leukotriens release test and the flow cytometric basophil activation test can be very helpful in diagnostics, especially when the skin prick test is contraindicated. The aim of this study was to evaluate the usefulness of antigen CD203c expression, as a marker of basophil activation by grass pollen or D. pteronyssinus antigens. Material and Methods: Peripheral blood from 13 allergic patients and nine healthy volunteers was analysed. Basophils activation was measured by the breakdown of antigen CD203c expression with Allergenicity Kit (Beckman Coulter), using Cytomics FC 500 flow cytometer (Beckman Coulter). Results: The sensitivity was 92,3% and specificity of test was 100%. 50.95 ± 15.7% of basophils (median 49.7%, 1.91–72.42%) were activated after grass pollen stimulation in atopic patients sensitised to this allergen, in comparison to 1.91% (0.00–7.96%) in control patients (p = 0.002). The percentage of activated basophils after D. pteronyssinus antigens stimulation was 40.6 ± 25.2% in allergic patients, compared to only 2.51 ± 1 96% of basophils from non-atopic controls (p = 0.0003). Basophils from 21 patients responded after anti-IgE stimulation (44.1 ± 18.9%), and none of the analysed samples was activated after PBS stimulation (2.03 ± 1.19%, p < 0.0001). Conclusions: These results demonstrate that basophil activation test based on antigen CD203c expression is very accurate in the diagnosis of atopic diseases.