title: Cerebrospinal fluid IL-21 levels in Neuromyelitis Optica and multiple sclerosis.
abstract: BACKGROUND
  Neuromyelitis optica (NMO) and multiple sclerosis (MS) are inflammatory demyelinating diseases of human central nervous system (CNS) with complex pathogenesis. IL-21/IL-21R regulates activation, proliferation and survival of both T cells and B cells, which are involved in the pathogenesis of NMO and MS. High levels of serum IL-21 were observed in NMO patients. However, concentration of cerebrospinal fluid (CSF) IL-21 in MS and NMO patients still remain unknown.
  
  
  OBJECTIVE
  To detect the CSF concentration of IL-21 in NMO and MS patients and to evaluate its relationship with disease activity, particularly concerned about its impact on humoral immunity.
  
  
  METHODS
  CSF IL-21 was detected by an enzyme-linked immunosorbent assay (ELISA) in NMO patients (n=21), MS patients (n=20) and controls (n=16).
  
  
  RESULTS
  CSF concentration of the IL-21 was noticeably elevated in NMO (p=0.012) and borderline significantly increased in MS (p=0.115). In addition, this occurrence was associated with humoral immune activity as shown by a correlation between IL-21 and complement in NMO cohort (p=0.023) and high IL-21 levels in autoantibody-positive subgroup (p=0.027).
  
  
  CONCLUSIONS
  The concentration of CSF IL-21 was noticeably elevated and might have a positive correlation with humoral immune activity in NMO.
authors.affiliation: Department of Neurology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China.
authors.forename: Aimin
authors.initials: A
authors.lastname: Wu
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Zhong
authors.forename: Honghao
authors.initials: H
authors.lastname: Wang
authors.forename: Wen
authors.initials: W
authors.lastname: Xu
authors.forename: Chen
authors.initials: C
authors.lastname: Cheng
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Dai
authors.forename: Jian
authors.initials: J
authors.lastname: Bao
authors.forename: Wei
authors.initials: W
authors.lastname: Qiu
authors.forename: Zhengqi
authors.initials: Z
authors.lastname: Lu
authors.forename: Xueqiang
authors.initials: X
authors.lastname: Hu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000974:Antibodies, Antinuclear / Q000097:blood; D034961:Antigens, Nuclear / Q000097:blood; D002648:Child; D003165:Complement System Proteins / Q000378:metabolism; D004185:Disability Evaluation; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007378:Interleukins / Q000134:cerebrospinal fluid*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D009471:Neuromyelitis Optica / Q000097:blood / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D055815:Young Adult; D000098546:Interleukin-21
chemical_list: D000974:Antibodies, Antinuclear; D034961:Antigens, Nuclear; D007074:Immunoglobulin G; D007378:Interleukins; D003165:Complement System Proteins; D000098546:Interleukin-21