Development of a monoclonal antibody-based competitive ELISA for detection of β-conglycinin, an allergen from soybean

Soybean β-conglycinin is one of the major food allergies for children and young animals. In order to detect immunoreactive β-conglycinin from soybean and soybean products, monoclonal antibodies against β-conglycinin were prepared using a conjugated chicken ovalbumin with a synthetic peptide that corresponded to one epitope sequence of β-conglycinin as the immunogen. The generated monoclonal antibodies, named as 6G4, 3B7, and 5F10, were identified as being of IgG1 isotype and exhibited high specificity to β-conglycinin. A competitive enzyme-linked immunosorbent assay (ELISA) based on monoclonal antibody 6G4 was established to determine β-conglycinin and showed an IC50 value of 4.7 ng/mL with a detection limit of 2.0 ng/mL. The recovery tests of β-conglycinin indicated that the monoclonal antibody 6G4-based competitive ELISA gave reliable reproducibility. Therefore, the produced monoclonal antibody 6G4 and the developed competitive ELISA could provide a valuable tool for sensitive determination of β-conglycinin and for future studies on food allergies related to soybean β-conglycinin.