Blood and CSF neurofilament light differentially detect neurodegeneration in early Alzheimer’s disease.
NEUROBIOLOGY OF AGING | JULY 25, 2020
Andersson E, Janelidze S, Lampinen B, Nilsson M, Leuzy A, Stomrud E, Blennow K, Zetterberg H and Hansson O.
Neurobiology of Aging. 2020.
This study was peformed using a Simoa® Homebrew assay.
Cerebrospinal fluid (CSF) neurofilament light (NfL) concentration has reproducibly been shown to reflect neurodegeneration in brain disorders, including Alzheimer’s disease (AD). NfL concentration in blood correlates with the corresponding CSF levels, but few studies have directly compared the reliability of these two markers in sporadic AD. Herein, we measured plasma and CSF concentrations of NfL in 478 cognitively unimpaired (CU) subjects, 227 patients with mild cognitive impairment (MCI), and 113 patients with AD dementia. We found that the concentration of NfL in CSF, but not in plasma, was increased in response to Aβ pathology in CU subjects. Both CSF and plasma NfL concentrations were increased in patients with MCI and AD dementia. Furthermore, only NfL in CSF was associated with reduced white matter microstructure in CU subjects. Finally, in a transgenic mouse model of AD, CSF NfL increased before serum NfL in response to the development of Aβ pathology. In conclusion, NfL in CSF may be a more reliable biomarker of neurodegeneration than NfL in blood in preclinical sporadic AD.