[The effect of bronchial allergen provocation on spontaneous production of histamine releasing factor (HRF) by mononuclear cells in patients with bronchial asthma].

The study was performed in 8 patients suffering from mild asthma. Bronchial allergen challenges with Dermatophagoides pretonyssinus were performed according to Chai et al method. Nonspecific bronchial reactivity to histamine (PC20H in mg/ml) were determined before the allergen challenge and in 90 min. and 24 hrs. after allergen provocation. Blood samples for mononuclear cells culture were collected before the trial and after the allergen challenge in 15, 90 min. and 8 and 24 hrs. The supernatants were assayed for HRF activity with basophils from a single donor. The significant increase of PC20H was observed xgPC20H in mg/ml 0.43 before allergen challenge and 0.08 and 0.125 after allergen provocation. Blood samples did not reveal any significant changes in HRF % activity--mean and SD before challenge test 47.7 16.2 and 49.9 15.0 in 15 min, 53.3 19.0 in 90 min, 56.6 15.8 in 8 hr, 52.5 20.4 in 24 hr after allergen provocation. The correlation between postallergen, nonspecific bronchial reactivity and spontaneous production of HRF activity was not found. The authors discuss the role of HRF in pathogenesis of nonspecific bronchial reactivity of asthmatic patients.