Methods: Eosinophils and basophils were obtained from subjects with asthma/CRS with and without alcohol sensitivity. Eosinophils were purified by density centrifugation and negative selection magnetic affinity purification. Basophils were studied using fresh whole blood isolates and basophils identified via flow cytometry as the CD123+ granulocyte population. Both cell lines were exposed to components of red wine including ethanol, red wine extract and two representative polyphenolic compounds, resveratrol and catechin. Evidence of granulocyte activation was then measured via flow cytometry and ELISA for basophils and eosinophils respectively.
Results: Basophil activation (upregulation of CD203c) was consistently seen with exposure to red wine extract but not with resveratrol. Further, in patients reporting alcohol sensitivity, high concentrations of alcohol (0.1%) induced basophil activation. This was not seen in basophils from patients without alcohol sensitivity. Additionally, subjects reporting sensitivity to alcoholic beverages reacted to catechin but not resveratrol. Studied eosinophil populations did not react to any of the experimental substances.
Conclusions: Reactivity to alcoholic beverages in subjects with CRS and asthma may reflect in part the ability of ethanol acting in synergy with the polyphenolic compound catechin to activate basophils. Sensitivity to alcoholic beverages does not appear to involve eosinophils or resveratrol.