Cross-reactivity of an anti-okadaic acid antibody to dinophysistoxin-4 (DTX-4), dinophysistoxin-5 (DTX-5), and an okadaic acid diol ester.

The cross-reactivity of the 6/50 monoclonal anti-okadaic acid antibody (mAb) to the recently discovered diarrhetic shellfish poisoning (DSP) metabolites dinophysistoxin-4 (DTX-4), dinophysistoxin-5 (DTX-5), and an okadaic acid (OA) diol ester was determined using a competitive indirect enzyme-linked immunosorbent assay (ELISA). The reactivity of the antibody to these molecules was compared to that with OA; the 6/50 mAb recognized all of these DSP compounds with equal sensitivity within the working range of the antibody (10-100 nM for OA). This confirms the ability of the antibody to detect all DSP compounds when used in analyses including ELISA and immunocytochemistry.