Performance evaluation of allergen specific IgE antibodies measurement using capture enzyme linked immunosorbent assay

Abstract

Objective To evaluate the performance of common inhalant allergen specific IgE antibodies (sIgE) measurement using capture enzyme-linked immunosorbent assay (ELISA), Fooke™ system. Methods The performance of Fooke™ system was evaluated according to the CLSI EP documents. Specific IgE to 6 common inhalant allergens, Dermatophagoides pteronyssinus (d1), Dermatophagoides farina (d2), cat epithelium and dander (e1), dog epithelium and dander (e5), Alternaria Alternata (m6) and mugwort pollen (w6), were measured by Fooke™ system. The precision, sensitivity, and linearity range were assessed. The results were compared with ImmunoCAP® system, collecting the compared samples from clinical patient serum from 25 May 2016 to 30 June 2016. Results The within run CVs of the 6 allergens were 3.60%-6.53%, and total CVs were 3.57%-7.46%, lower than the stated. Limit of quantitative determination was <0.35 KU/L, lower than the sensitivity stated. The linearity range of d1 and m6 was 0.37-94.30 KU/L (R2=0.999, P<0.001) and 0.35-89.80 KU/L (R2=0.998, P<0.001), which demonstrated a sound linear correlation.In the method comparison tests, the quantitative results between Fooke™ and ImmunoCAP® system had obvious linear correlation, R2 of d1, d2, e1, e5, m6 and w6 was 0.356, 0.473, 0.847, 0.478, 0.254 and 0.355, respectively, P<0.001. The negative, positive and overall agreement ratio of qualitative results was 99.2% (944/952), 82.1% (528/643) and 92.3% (1 472/1 595), with high level of agreement (Kappa=0.835, P<0.001). The ranked agreement ratio was 91.5% (1 459/1 595). Conclusions Fooke™ system (Capture ELISA) is domestically produced, automated and quantitative allergen sIgE detecting system, which showed high precision and sensitivity, and sound correlation with ImmunoCAP® system, meeting the testing requirement. Fooke™ system has practical value, which is a new option for clinical application.(Chin J Lab Med, 2016, 39: 824-828) Key words: Allergens; Immunoglobulin E; Enzyme-linked immunosorbent assay; Immunoenzyme techniques