A Simple and Rapid Light-Initiated Chemiluminescence Assay for Quantitation of Artemisia-Specific Immunoglobulin E.

ABSTRACT

BACKGROUND: Light-initiated chemiluminescence assay (LICA) is a homogeneous assay that has been successfully used for the quantitation of food allergen-specific immunoglobulin E (sIgE), but not inhaled allergen-sIgE. Simultaneously, current assays used to detect allergen-sIgE are serum consuming and/or time consuming. Hence, we established a method for the quantitation of Artemisia-sIgE based on LICA and verified its performance according to the clinical guideline documents, laying a foundation for the quantitation of inhaled and food allergen-sIgE in parallel on LICA. METHODS: The assay was established after optimizing the first incubation time and the dilutions of Artemisia-coated chemibeads, biotinylated goat anti-human IgE, and serum. In order to quantitate Artemisia-sIgE, the calibration curve was established with a high positive serum of known concentration. The assay performance was confirmed per the clinical guideline documents. In addition, the correlation between the results of LICA and capture enzyme-linked immunosorbent assay was evaluated. RESULTS: The developed LICA's coefficients of variation of repeatability and intermediate precision were 3.20%, 2.14%, and 3.85% and 4.30%, 4.00%, and 4.40%, respectively. The limit of detection was 0.10 kUA/L, and the limit of quantitation was 0.11 kUA/L. The range of linearity was from 0.27 kUA/L to 97.53 kUA/L (r = 0.9968). The correlation coefficient (r) for the correlation analysis between results of LICA and capture ELISA was 0.9087. This assay was successfully applied in 64 human serum samples, showing good sensitivity (82.20%) and specificity (100%). CONCLUSION: An Artemisia-sIgE quantitation assay based on LICA was successfully established. Its performance satisfied the clinical requirements and could be widely used in clinical laboratories.