PRIMING OF EOSINOPHIL ADHESION IN PATIENTS WITH BIRCH POLLEN ALLERGY DURING POLLEN SEASON - EFFECT OF IMMUNOTHERAPY

The adhesion of eosinophil granulocytes to E-selectin, vascular cell a dhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (IC AM-1) was investigated before and during birch pollen season in 24 pat ients allergic to birch pollen who had rhinoconjunctivitis and, in hal f of the cases, asthma during season, Half of the patients were underg oing specific immunotherapy for birch pollen allergy, Increased adhesi on to VCAM-1 and ICAM-1 (p < 0.05) during season as compared with befo re season was demonstrated by eosinophils of patients in the control g roup and by eosinophils of the patients without asthma treated with im munotherapy, but not by eosinophils from the immunotherapy-treated pat ients with asthma, Eosinophils from the control group of patients demo nstrated increased cell surface expression of CD18 and CD49d (p < 0.05 and p < 0.01, respectively) during season as compared with before sea son, and eosinophils from the immunotherapy-treated patients showed in creased cell surface expression of CD49d (p < 0.01) during season. Sim ultaneous measurement of neutrophil adhesion revealed increased adhesi on to E-selectin and ICAM-1 (p < 0.01) during season compared with bef ore season in the immunotherapy-treated group of patients, Neutrophils from the control subjects without asthma showed increased adhesion to E-selectin (p < 0.05) during season, In conclusion, eosinophils from patients allergic to birch pollen demonstrated priming of the adhesion to VCAM-1 and ICAM-I during birch pollen season, Immunotherapy treatm ent prevented the priming of eosinophil adhesion during pollen season in the patients allergic to birch pollen who had asthma, but not in th ose without asthma. In contrast, neutrophils from the immunotherapy-tr eated patients, both with and without asthma, demonstrated priming of the adhesion to E-selectin and ICAM-1 during season. The latter result s indicate that immunotherapy, in case of the patients allergic to bir ch pollen with asthma induced a shift from the production of primarily eosinophil priming agents to primarily neutrophil I,riming agents, wh ich may be caused by a shift from Th2 to Th1 lymphocytes.