Comparison of an automated microfluidic immunoassay technology (BioIC, lab-on-chips) and ImmunoCAP assay. Lab-on-chips as a tool for specific IgE (sIgE) detection

Introduction
The measurement of clinically important specific IgE (sIgE) antibody is pivotal for both diagnosis and management of allergy. Two methods may be distinguished depending on the number of antigens tested simultaneously: singleplex and multiplex. BioIC is a multiplex, advanced, automated microfluidic immunoassay system enabling simultaneous sIgE measurement against multiple allergens. ImmunoCAP is a singleplex assay for sIgE detection and gold standard method for diagnosis of allergy.

Aim
To compare and validate the diagnostic capability of a multiplex sIgE assay – BioIC assay with a singleplex ImmunoCAP assay.

Material and methods
Using both BioIC assay and ImmunoCAP assay, the sIgE level in serum samples from 20 allergic disease patients with respect to 33 allergens (16 inhalant allergens, 16 food allergens and 1 contact allergen) was measured. Receiver operating characteristic (ROC) area under the curve (AUC), qualitative and semi-quantitative comparisons were performed to compare both sIgE measurement methods using statistical analyses.

Results
ROC AUC analysis showed similar sensitivity and specificity of BioIC assay and ImmunoCAP assay. In qualitative analysis, the negative and positive agreements were 100% equal for each allergen. Spearman’s rank correlation coefficients identified very high positive correlations between two assays for all tested allergens (p < 0.001).

Conclusions
The BioIC showed agreement with ImmunoCAP assay. Sensitivity and specificity of both assays are similar, thus they showed similar diagnostic performance. However, careful interpretation of obtained results is necessary in clinical applications because of methodological differences between these two systems.