Allergen concentrations optimization for basophil activation test

N.V. Bychkova^1,2, A.E. Uchevatkina³, Ya.I. Kozlova³, E.V. Frolova³, G.A. Novik⁴, N.M. Kalinina<sup>1,2

1</sup>Nikiforov All-Russian Center for Emergency and Radiation Medicine, Saint Petersburg
²Pavlov First St. Petersburg State Medical University
³North-Western State Medical University named after I.I. Mechnikov, Saint Petersburg
⁴Saint Petersburg State Pediatric Medical University

Cell function testing, for which an optimal conditions selection has proceeded, has been recently proposed to improve the possibility of sensibilization detection to such allergen types as food, drug, inhalation. Basophil activation test is considered as a provocation in vitro test. It showed high sensitivity and specificity to a large range of allergens.
Aim: to study an allergen concentration impact on basophil activation in vitro in different patient groups.
Patients and Methods: 5 patients with allergic bronchopulmonary aspergillosis, 9 patients with atopic asthma without mycetogenic sensitization, 11 patients with atopic dermatitis (6 — with sensitization to wheat flour allergen, and 5 — without it) were examined. Laboratory examination included determination of the specific IgE level and basophil activation in vitro test by flow cytometry with allergen concentrations (Alkor Bio, Russia) from 0.5 to 100 µg/ml.
Results: the number of activated basophils expressing CD203c advanced with the allergens concentration increase in the samples. The value of choosing the optimal allergens concentration of Aspergillus fumigatus and wheat flour in the basophil activation test to exclude false positive and false negative results was demonstrated. The method accuracy improvement requires low activation index to increase sensitivity and low but sufficient allergen concentration used for the specificity increase to activate basophils. The optimal concentrations range for both allergens in the basophil activation test was from 2 to 10 µg/ml. It was shown that the cells activation degree in interaction with a mycotic allergen is higher than with food.
Conclusion: detection of patient sensitization in basophil activation test using the allergen optimal dosage coincides with the history data, skin test positive results and the level of specific IgE to allergens.

Keywords: allergic diseases, sensitization, basophil activation test, concentration, allergens, IgE, allergic bronchopulmonary aspergillosis, atopic dermatitis.
For citation: Bychkova N.V., Uchevatkina A.E., Kozlova Ya.I. et al. Allergen concentrations optimization for basophil activation test. RMJ. 2019;3:32–35.