3-HAA	3-hydroxyanthranilic acid
3-HAO	3-hydroxyanthranilate oxidase
3-HK	3-hydroxy-l-kynurenine
9HP	9-hole peg test
AA	anthranilic acid
AD	Alzheimer’s disease
AMPA	α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid
Aβ	β-amyloid
BBB	blood–brain barrier
BICAMS	brief international cognitive assessment for multiple sclerosis
BVMT-R	brief visuospatial memory test
CDA	confirmed disability accumulation
CGRP	calcitonin gene-related peptide
CI	cognitive impairment
CIS	clinically isolated syndrome
CNS	central nervous system
CVLT-II	California verbal learning test
CSF	cerebrospinal fluid
DMT	disease modifying therapy
EAE	experimental autoimmune encephalomyelitis
ECL	electrochemiluminscent assay
EDSS	expanded disability status scale
ELISA	enzyme-linked immunosorbent assay
GPR35	orphan G-protein coupled receptor
HTT	huntingtin gene
IDO	indolamine 2,3-dioxygenase
IFN-γ	interferon-γ
JCV	John Cunningham virus
KAT	kynurenine aminotransferase
KMO	kynurenine 3-monooxygenase
KP	kynurenine pathway
KYNA	kynurenic acid
L-KYN	L-kynurenine
LP	lumbar puncture
mCGL	macular ganglion cell layer
MHC	major histocompatibility complex
MRI	magnetic resonance imaging
MS	multiple sclerosis
MSFC	multiple sclerosis functional composite
NAD+	nicotinamide adenine dinucleotide
NADP+	nicotinamide adenine dinucleotide phosphate
NEDA	no evidence of disease activity
NfL	neurofilament
NMDA	N-methyl-d-aspartate
OCT	optical coherence tomography
ON	optic neuritis
OPN	osteopontin
PASAT	paced auditory serial adding test
PD	Parkinson’s disease
PetCO2	end-tidal partial pressure of CO2
PIRA	progression independent from relapse activity
PIRMA	progression independent from relapse and MRI activity
PNS	peripheral nervous system
PPAR-γ	peroxisome proliferator-activated receptor-γ
PPMS	primary progressive multiple sclerosis
QoL	quality of life
QUIN	quinolinic acid
RA	radial artery
RGC	retinal ganglion cell
RIS	radiologically isolated syndrome
RNFL	retinal nerve fiber layer
ROS	reactive oxygen species
RRMS	relapsing-remitting multiple sclerosis
SDMT	symbol digit modalities test
SiMoA	single molecular array
SPMS	secondary progressive multiple sclerosis
STA	superficial temporal artery
T25W	timed 25-feet walk test
TDO	tryptophan 2,3-dioxygenase
TNF-α	tumor necrosis factor-α
Trp	tryptophan
VMCA	blood flow velocity of the middle cerebral artery
WBA	whole brain atrophy
WHO	World Health Organization