Estimation of the allelic status of apolipoprotein E4 isoforms with fully automated LUMIPULSE® assays

Aim: Apolipoprotein E (ApoE) isoforms, especially the ApoE4 isoform, are genetic risk factors for Alzheimer’s disease (AD). Moreover, the APOE ε4 haplotype has a dose-dependent association with an increased risk of amyloid-related imaging abnormalities (ARIA) in individuals receiving disease-modifying therapy for AD. Therefore, the importance of APOE genotyping or proteotyping has been highlighted. Here, the authors developed fully automated chemiluminescence enzyme-immunoassay kit for ApoE4 and Pan-ApoE, and evaluated their diagnostic concordance with the APOE genotyping. Methods: One hundred seventy-eight specimens were analyzed using the Lumipulse® G ApoE4 and Pan-ApoE for the ApoE proteotype and evaluated its diagnostic concordance with the APOE genotype. Results: The ApoE4 kit specifically detected the ApoE4 concentration in plasma samples, and the polymorphism could be classified clearly by the ratio of ApoE4 and Pan-ApoE amount in plasma. Conclusions: The combination of Pan-ApoE and ApoE4-specific chemiluminescent enzyme immunoassay (CLEIA) assay is useful for predicting APOE ε4 allele status.