Cognitive variability as a potential biomarker for incident mild cognitive impairment and Alzheimer's disease: An ADNI data analysis

oligomeric form of tau in CSF. Finally, we performed double-blind analysis of tau oligomers in 171 CSF samples by direct ELISA. The results indicate that the ratio of total tau/tau oligomers is a reliable biomarker and can distinguish between AD, MCI-AD, MCI, and controls. Moreover, we demonstrate that tau oligomer levels in the serum increase shortly after the intravenous administration of an anti-tau oligomer specific antibody to transgenic animals expressing human tau.Conclusions:Our results validate tau oligomers as a reliable biomarker for AD and tauopathies. These assays are suitable for analysis of human CSF samples and may be critical for early diagnosis and the evaluation of AD clinical trials. Moreover, standardization of tau oligomer measurements may be crucial for the guidance and facilitation of drug development.