NEFL and Parkinson disease: A previous study assessing 160 AD, PD, CBS, PSP, FTD, and MSA patients and 30 controls tested nine potential CSF biomarkers: T-tau, p-tau, Aß42, NfL, ?-synuclein, YKL-40, MCP-1, and soluble amyloid precursor protein α and β (sAPPα and sAPPβ).77