Development of Enzyme-Linked Immunosorbent and Immunochromatography Assays for Diagnosing Nosema ceranae Infection in Honey Bees.

Nosema ceranae ( N. ceranae ) infection is prevalent globally, causing a decline in bee populations and significant economic losses to apiarists. Although several methods have been proposed for diagnosing Nosema infections, limitations in these methods have hindered their broad applications. Therefore, this current study aimed to develop a specialized method for diagnosing Nosema infections. To achieve this, a sandwich enzyme-linked immunosorbent assay (ELISA) and immunochromatography assay (ICG) were developed, and their effectiveness in screening and diagnosing Nosema infection was assessed. In sandwich ELISA, the combination of the monoclonal antibodies (mAb) 19B2 and biotinylated-19B2 exhibited stronger binding affinity to the antigen than did other combinations of mAbs that were tested. Furthermore, the antigen detection limit achieved with the sandwich ELISA surpassed that previously reported with Western blotting. The ICG was designed using the same antibody combination as that used in sandwich ELISA; however, the assay exhibited a lower diagnostic ability for Nosema infection than the ELISA. The diagnostic models developed in this study offer practical applications for conducting rapid nosemosis detection tests. These innovative techniques will help to improve the timely identification and management of nosemosis.