Cell-ELISA detection of antineuronal antibodies in central nervous system involvement in systemic lupus erythematosus.
OBJECTIVE
To develop a cell-ELISA method to detect antineuronal antibodies (anti-Ns) and evaluate the diagnostic value of anti-Ns in central nervous system involvement in systemic lupus erythematosus (CNS-SLE).


METHODS
Anti-N was assessed in both serum and cerebrospinal fluid (CSF) samples from 38 patients with CNS-SLE, 29 with SLE without CNS involvement (non-CNS-SLE), 36 with other rheumatic diseases and 59 with non-rheumatic diseases with the CNS manifestations using a cell-ELISA method with 1% paraformaldehyde-fixed SK-N-MC neuroblastoma cells as substrate. Serum samples from 37 healthy donors were also included in this study. Patients with CNS-SLE who were anti-N positive in CSF were studied serially for CSF anti-N levels at times of treatment-associated improvement in CNS symptoms.


RESULTS
Serum anti-N levels were significantly increased in patients with SLE compared with other groups, with a sensitivity of 61.2% (41/67) and a specificity of 91.8% (p<0.001). CSF anti-N levels were significantly increased in patients with CNS-SLE, with a sensitivity of 47.4% (18/38) and a specificity of 89.7%, whereas only 10.3% (3/29) of patients with non-CNS-SLE had increased anti-N in CSF (p<0.001). CSF anti-N levels decreased significantly after effective treatment of CNS-SLE (p<0.05).


CONCLUSIONS
Serum anti-N is relatively specific to SLE. CSF anti-N is a sensitive and relatively specific antibody in diagnosing CNS-SLE and correlates with CNS-SLE activity.
Zhang
Xuan
X
Department of Rheumatology and Immunology, Peking Union Medical College Hospital, 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China.
Shu
Huijun
H
Zhang
Fengchun
F
Tian
Xinping
X
Dong
Yi
Y
D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000032:analysis* / Q000097:blood / Q000134:cerebrospinal fluid; D015415:Biomarkers / Q000097:blood / Q000134:cerebrospinal fluid; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D020945:Lupus Vasculitis, Central Nervous System / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000276:immunology*; D012680:Sensitivity and Specificity
D001323:Autoantibodies; D015415:Biomarkers