A novel triple mix radiobinding assay for the three ZnT8 (ZnT8-RWQ) autoantibody variants in children with newly diagnosed diabetes

▶ We have re-cloned the ZnT8-R cDNA into a high efficiency in vitro transcription-translation plasmid. ▶ We have subjected the ZnT8-R cDNA to site-directed mutagenesis to generate the ZnT8-W and ZnT8-Q variants. ▶ We have tested a novel ZnT8-TripleA assay to screen for circulating ZnT8A against any of the three variants. ▶ The ZnT8-TripleA assay showed a low false positive rate and a negligible false negative rate. ▶ This assay represents a highly reproducible practical alternative to individual RBA in newly diagnosed diabetes children.