AD	Alzheimer’s disease
ALS	Amyotrophic lateral sclerosis
Aβ	Amyloid β
BACE1	Beta-site APP-cleaving enzyme 1
BBB	Blood–brain barrier
CCH	Chronic cerebral hypofusion
CIS	Clinically isolated syndrome
CNS	Central nervous system
CSF	Cerebrospinal fluid
DS	Down syndrome
EBV	Epstein–Barr virus
EOAD	Early-onset Alzheimer’s disease
FLC	Immunoglobulin-free light chains
HLA	Human leukocyte antigen
KFLC	Kappa-free light chains
LFLC	Lambda-free light chains
LOAD	Late-onset Alzheimer’s disease
MCI	Mild cognitive impairment
miRNAs	microRNAs
MMPs	Matrix metalloproteinases
MS	Multiple sclerosis
NDs	Neurodegenerative diseases
Nf-L	Neurofilament light chains
NFTs	Neurofibrillary tangles
NF-κB	Nuclear factor κB
NGS	Next-generation deep sequencing
PD	Parkinson’s disease,
pNfH	Phosphorylated neurofilament heavy chains
PPMS	Primary progressive MS
pTau	Phosphorylated tau
pTau181	Tau phosphorylated at threonine 181
ROS	Reactive oxygen species
RRMS	Relapsing–remitting MS
SOD1	Superoxide dismutase 1
SPMS	Secondary progressive MS
TDP-43	Transactive response DNA-binding protein 43 kDa
tTau	Total tau protein