An enzyme-linked immunosorbent assay for detection of botulinum toxin-antibodies.

INTRODUCTION: Antibodies against botulinum neurotoxin (BNT-AB) can be detected by the mouse protection assay (MPA), the hemidiaphragm assay (HDA), and by enzyme-linked immunosorbent assays (ELISA). Both MPA and HDA require sacrifice of experimental animals, and they are technically delicate and labor intensive. We introduce a specially developed ELISA for detection of BNT-A-AB and evaluate it against the HDA. METHODS: Thirty serum samples were tested by HDA and by the new ELISA. Results were compared, and receiver operating characteristic analyses were used to optimize ELISA parameter constellation to obtain either maximal overall accuracy, maximal test sensitivity, or maximal test specificity. When the ELISA is optimized for sensitivity, a sensitivity of 100% and a specificity of 55% can be reached. When it is optimized for specificity, a specificity of 100% and a sensitivity of 90% can be obtained. RESULTS: We present an ELISA for BNT-AB detection that can be-for the first time-customized for special purposes. Adjusted for optimal sensitivity, it reaches the best sensitivity of all BNT-AB tests available. CONCLUSIONS: Using the new ELISA together with the HDA as a confirmation test allows testing for BNT-AB in large numbers of patients receiving BT drugs in an economical, fast, and more animal-friendly way.