Что пишут в мире об ALEX²?


Тест на ингибирование перекрестно-реактивной углеводной детерминанты (CCD) может помочь определить ложноположительный результат для растительного аллергена - SIgE, вызванного CCD

Wenting L; Sun B; Wu Z

Background : Pollen allergens are important inhaled allergens andcan cause respiratory allergic diseases, especially seasonal allergic rhinitis and asthma. Many pollen allergen and seed have the glycoprotein epitope, the specific IgE (sIgE) tests are often affected by cross- reactive carbohydrate determinant (CCD), cause false- positive reactions. This study analyzed the sensitization of pollen allergens in south China and discussed the effect of CCD inhibitor on the results of sIgE test of pollen allergens. Thus, the objective of this study was to investigate the level and feature of serological IgE cross- reactivity between grass pollen and seed in a cohort of respiratory allergic patients in Southern China.
Method : Two hundred and thirteen patients, with a doctor ' s diagnosis of allergic rhinitis or asthma, IgE towards at least two common inhaled allergens were recruited. Serum samples were analyzed for IgE against tree mix (willow/poplar/elm Tree), common ragweed, mugwort, humulus scandens, peanut, soy, and cross- reactive carbohydrate determinants (CCD) and specific IgE- binding inhibition experiments were performed.
Results : Among the patients sensitized to multiple allergens, 83 patients (39.0%) were plant allergen sensitization (sIgE positive for any of the above six allergens was defined as plant allergen sensitization, PAS), and 57.8% of PAS patients were positive to CCD- sIgE. PAS subjects were more often sensitized to CCD, known to be crossreactive between grass and seeds. CCD inhibited binding to all pollen and seed allergen by 73% to 100% (Table 1). The highest inhibition rate was obtained for Humulus scandens, followed by mugwort and peanut (both 85.2%), common ragweed (81.5%), soy(80.0%) and tree mix (73.0%). It was surprised to find that all sIgE against to pollen and seeds from 23 PAS patients were turned to negative after CCD inhibition.
Conclusion : CCD was positive in the serum of most plant allergensIgE positive patients in South China. More than 73% plant allergenssIgE were eliminated into negative after CCD inhibition experiment, suggesting majority the plant allergic patients in southern China, particularly the sIgE against peanut, soybean and pollen allergens, were false- positive caused by the CCD interference. CCD inhibition test should be used in clinical diagnosis, which can help to avoid misdiagnosis of plant allergens.