CAST-ELISA TEST IN DIAGNOSIS OF MITE ALLERGY

The recently developed CAST-ELISA method was applied to determine alle rgen-induced leukocyte stimulation. This method is based on the measur ement of sulfidoleukotriene secretion by peripheral blood leukocytes s timulated with specific allergen in the presence of interleukin 3. 23 patients allergic to Dermatophagoides pteronyssinus were included in t his study. All subjects received no medication 2 weeks before the test ing. Leukocytes were isolated by dextran sedimentation. After incubati on with allergen the cells were centrifuged and the concentration of s ulfidoleukotrienes in supernatant was determined. The results were exp ressed in pg/ml after subtracting the values of spontaneous sulfidoleu kotriene production in portions incubated without allergen. We observe d a wide range of sulfidoleukotriene secretion upon allergen stimulati on. Concentrations of leukotrienes ranged from 0 to 3440 pg/ml. The me an level in the whole group was 1521.3 pg/ml at the optimal allergen c oncentration. Positive results were observed in 21 subjects. In 2 subj ects we could not demonstrate leukotriene secretion by stimulation wit h allergen. 15 healthy control subjects were also included in this stu dy. 12 subjects had negative skin prick tests (SPT) as well as CAST re sults. In 2 healthy subjects with positive SPT, we also observed posit ive CAST results. However, leukotriene secretion was lower than 300 pg /ml in these subjects. We conclude that CAST-ELISA is a valuable metho d for determining the allergic status in patients with mite allergy.