ヒトIgA に対するイムノクロマトグラフィーの開発

Abstract

Immunochromatography (ICG) strip test based on monoclonal antibodies (mAbs) conjugated with gold nanoparticles was developed and its application for primary screening of IgA in human saliva was evaluated. Six mAbs were established against human secretory IgA. anocolloidal gold as the detection reagent was labelled with mAb ④. MAb ⑥ was immobilized on a nitrocellulose membrane as the capture reagent to prepare the ICG strip test. After reaction of mAb ④-nanocolloidal gold probe with IgA in saliva, resulting immune complex was vertically developed, captured by mAb ⑥ immobilized on the membrane and visualized as a gold band. In the optimized investigational conditions, the ICG strip test could distinguish human secretory IgA in the range from 1 to 20 μg/mL and was sufficiently sensitive to find out incomplete IgA deficiency from salivary screening. It took only 10 minutes to accomplish a detection of salivary IgA in this assay, compared to 5 hours by sandwich ELISA.