Marked increase in cerebrospinal fluid glial fibrillar acidic protein in neuromyelitis optica: an astrocytic damage marker.
BACKGROUND
Neuromyelitis optica (NMO) is a neurological inflammatory disease associated with autoimmunity to aquaporin 4, predominantly localised in astrocytic foot processes. Recent studies have revealed that loss of aquaporin 4 and glial fibrillar acidic protein (GFAP) is a prominent feature of NMO lesions, suggesting astrocytic impairment.


OBJECTIVE
To reveal a useful clinical biomarker of NMO.


METHODS
Enzyme-linked immunosorbent assays were carried out for astrocytic markers GFAP and S100B in CSFs, obtained from the patients with NMO (n = 10) and multiple sclerosis (MS) (n = 10) manifesting acute myelitis, acute disseminated encephalomyelitis (ADEM) (n = 3), spinal infarction (n = 3), and other neurological diseases (OND) (n = 5).


RESULTS
The CSF-GFAP levels during relapse in NMO (7666.0 (SD 15 266.5) ng/ml) were significantly over several thousand times higher than those in MS (0.7 (1.5)) or OND (0.6 (0.3)), and considerably higher than those in spinal infarction (354.7 (459.0)) and ADEM (0.4 (0.2)). They returned close to normal levels along with clinical improvement soon after corticosteroid therapy in NMO. There were strong correlations between the CSF-GFAP or S100B levels and expanded disability status scales or spinal lesion length in NMO (r>0.9).


CONCLUSIONS
CSF-GFAP and S100B may be clinically useful biomarkers in NMO, and astrocytic damage is strongly suggested in the acute phase of NMO.
Department of Neurology, Tohoku University Graduate School of Medicine, Aobaku, Sendai, Japan. misu@em.neurol.med.tohoku.ac.jp
T
T
Misu
R
R
Takano
K
K
Fujihara
T
T
Takahashi
S
S
Sato
Y
Y
Itoyama
D000328:Adult; D000368:Aged; D051401:Aquaporin 4 / Q000235:genetics; D001253:Astrocytes / Q000473:pathology*; D015415:Biomarkers; D004673:Encephalomyelitis, Acute Disseminated / Q000134:cerebrospinal fluid; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000134:cerebrospinal fluid*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000134:cerebrospinal fluid*; D009418:S100 Proteins / Q000134:cerebrospinal fluid; D013116:Spinal Cord / Q000473:pathology
D051401:Aquaporin 4; D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins