Establishment of a method for serological analysis of three major house dust mite (HDM) allergenic components-sIgE based on light-initiated chemiluminescence assay (LiCA) provides a deeper understanding of the clinical symptoms of allergic diseases.

Initially, the reaction conditions were optimized, and the levels of sIgE specific to the major HDM components-Der p 1, Der p 2, and Der p 23-were measured using the Light-initiated Chemiluminescence Assay (LiCA) assay. The performance of this assay was evaluated in accordance with established clinical guidelines. Subsequently, we analyzed the distribution of these components among 90 children with various allergic diseases.

Der p1-carboxy microspheres, Der p 2-carboxy microspheres, and Der p 23-aldehyde microspheres were selected for coupling and binding to detect the chemiluminescence signals and calculate the signal-to-noise ratios(S/N), respectively. 45 min was selected as the optimal reaction time for the first stage. The reaction time of the second stage was 10 min, and the total reaction time was 55 min. Coefficients of variation(CV) for repeatability ranged from 2.64% to 9.36%, and intermediate precision from 5.77% to 9.89%. No matter the repeatability or intermediate precision, the CV value was less than 15%, which was considered acceptable.

A total of 90 patients were screened in this study, 66 males (73.33%) and 24 females (26.67%) with mean age of 8.50±3.31 years .The positive values of the other two HDM components sIgEs in female patients were slightly higher than that in males, except for Der p 2, but none of the disparities was statistically significant (p > 0.05). The majority had allergic rhinitis (94.44%), followed by allergic asthma (60%) and allergic skin disease (8.89%). Of the 90 Der p-positive children, 81(90%) of the patients were positive to either one of the three major components. Specifically, 58 (64.44%) were sensitized to Der p1, 68 (75.56%) were sensitized to Der p2. Only 11 children (12.22%) tested positive for Der p 23. Notably, Of these 11 Der p 23-positive children, none were positive to Der p23 alone. The proportion of Der p2 detection in patients with a class four or higher sIgE response to Der p was over 90% and with higher concentration of Der p-sIgE, Der p 2 positive rate also will increase. We then investigated co-sensitization among the three HDM components. It revealed that the highest cosensitization rate in the HDM components group was Der p 1 and Der p 2, with a total of 37 subjects' co-sensitization (41.11%). 8 (8.89%) of patients were sensitized to the three components while 40(44.44%) were sensitized to two out of three (41.11% to Der p 1 and Der p 2; 2.22% to Der p 1 and Der p 23; 1.11% to Der p 2 and Der p 23). We also found that Der p 23-sIgE levels among different age groups showed distinct differences among the toddler period (>1-3 years), the preschool period (>3-7 years), the school-age (7–12, years) period and the adolescence period (>12-18 years). IgE levels of Der p 23 were highest in the adolescence group (P=0.010, χ2=10.333 ). IgE levels of Der p 2 were highest in the adolescent group, while IgE level of Der p 1 was highest in the toddler group, but there were no significant difference between the four groups. 

In our study population, the mean number of positive components was 1.52. Patients with combined asthma and rhinitis were sensitive to more components than those with asthma only. Then we analyze the relationship between the positive frequency of three HDM components and the allergic symptoms. We find that Der p 23 was significantly higher in asthmatics (P < 0.05). In the relationship between the complexity of allergic symptoms and the HDM components, we observed a strong sensitization of Der p 23 among patients with a single symptom to multiple symptoms compared with other components. 

A HDM components-sIgE quantitation assay based on LiCA was established, which could be used as a new reliable analytical tool for the determination of HDM components-sIgE. Der p2 is the most common component in HDM-associated allergic diseases, and Der p 23 is associated with the development of asthma and more complex allergic manifestations. component resolved diagnostics is better in clinical diagnostic performance.