A novel lectin-based enzyme-linked immunosorbent assay for the measurement of IgA1 in serum and secretory IgA1 in secretions.

Jackfruit lectin (Jacalin) specifically binds IgA1 and secretory IgA1 (sIgA1). Jacalin was successfully purified, and used as the immobilized phase in novel noncompetitive enzyme-linked immunosorbent assays (ELISAs) for the measurement of IgA1 in serum and sIgA1 in saliva, using jacalin affinity purified material as standards. A non-competitive ELISA for the measurement of total sIgA was also developed using commercially available reagents.