NEFL and Alzheimer disease: In summary, two biomarkers of amyloidosis (reduced CSF Aβ42 in CSF and PET brain amyloid imaging) and biomarkers of neurodegeneration (increased T-tau and P-tau, NfL, and VILIP-1 in CSF, atrophy on structural MRI, and hypometabolism measured by FDG PET) are sufficiently validated for inclusion in the clinical diagnosis of AD and monitoring the effects of therapy [124,125].