Paradoxical increase of IgE binding components during allergen-specific immunotherapy in pollinosis patients

Abstract

Allergen-specific immunotherapy (SIT) reduces allergen specific IgE (sIgE) levels and achieves clinical and immunological tolerance by modulating innate and adaptive immunological responses. Increased temperature and CO2 concentrations caused by climate changes contribute to an increase of pollen count and allergenicity that influences clinical SIT outcomes. In this study, we investigated the changes of IgE binding components to tree and weed pollens in pollinosis patients who showed a paradoxical increase of serum sIgE level during pollen-SIT. We enrolled nine patients who showed an increasing pattern of serum sIgE level to alder, birch, ragweed and mugwort pollens by enzyme-linked immunosorbant assay. IgE immunoblot analysis confirmed the intensification or new generation of major IgE binding components that could be induced by climate change. The findings suggest that the regular monitoring of sIgE levels and symptom changes is required to improve the clinical outcomes of SIT in patients undergoing SIT for tree and weed pollens.

Keywords: Climate Change; Immunotherapy; Pollinosis; Specific IgE.

Fig. 1

Changes of serum sIgE levels to tree and weed pollen extracts by ELISA. A Wilcoxon signed rank test indicates significant increase of sIgE levels to alder (A, from 1,110 ±1,234 to 1,938±1,065, P = 0.001), birch (B, from 1,201±1,495 to 1,994±1,290, P = 0.006), ragweed (C, from 401±677 to 1,490±986, P = 0.001) and mugwort (D, from 1,281±1,309 to 2,052±1,186, P = 0.001). Dashed line indicates cutoff values (172.7 in alder, 199.6 in birch, 186.2 in ragweed and 223.4 in mugwort). sIgE, specific IgE; ELISA, enzyme-linked immunosorbant assay.

Fig. 2

Changes of IgE binding components to tree and weed pollen extracts by immunoblotting. (A) In alder pollen, two patients (No. 1, 2) show new generations of IgE binding components to major allergen and additional components, and one (No. 3) shows a new generation of additional components. (B) In birch pollen, two patients (No. 1, 5) show a new generation of IgE binding components to major allergen and additional components; however, one patient (No. 4) shows a new generation of additional components. (C) Various changes of IgE binding component to major allergen (not changed in patient No. 6, decreased in No. 7, and intensified in No. 8) are noted in ragweed pollen along with a new generation of additional components that ranged from 9-13 kDa. (D) In mugwort pollen, a new generation of IgE binding components to both of major allergen and additional components (No. 1) and intensification of IgE binding components to major and additional components (No. 9) are noted. Major band was defined as below; Aln g 1 (17 kDa) in alder, Bet v 1 (17 kDa) in birch, Amb a 1 (38 kDa) in ragweed and Art v 1 (24 kDa) in mugwort.