title: Association between soluble L-selectin and anti-JCV antibodies in natalizumab-treated relapsing-remitting MS patients.
abstract: OBJECTIVE
  In relapsing-remitting MS (RRMS) patients treated with natalizumab, the low level of L-selectin-expressing CD4+ T cells has been associated with the risk of progressive multifocal leukoencephalopathy (PML). In this study, our aim was to correlate the levels of soluble L-selectin and the anti-JCV antibody index in the sera of RRMS patients treated with natalizumab.
  
  
  METHODS
  This study included 99 subjects, including 44 RRMS patients treated with natalizumab, 30 with interferon beta (IFN-β) and 25 healthy controls. The levels of soluble L-selectin (sL-selectin) in sera were measured by ELISA, and the anti-JC Virus (JCV) antibody index was determined by the second-generation ELISA (STRATIFY JCV™ DxSelect™) assay.
  
  
  RESULTS
  A significant correlation was found between the levels of sL-selectin and anti-JCV antibody indices in sera in the natalizumab-treated patients (r=0.402; p=0.007; n=44), but not in those treated with IFN-β. This correlation became even stronger in JCV seropositive patients treated with natalizumab for longer than 18 months (r=0.529; p=0.043; n=15).
  
  
  CONCLUSIONS
  The results support the hypothesis of sL-selectin being connected to the anti-JCV antibody index values and possibly cellular L-selectin. Measurement of serum sL-selectin should be evaluated further as a potential biomarker for predicting the risk of developing PML.
authors.affiliation: Neuroimmunology Unit, Medical School, University of Tampere, Tampere, Finland.
authors.forename: Pabitra
authors.initials: P
authors.lastname: Basnyat
authors.affiliation: Neuroimmunology Unit, Medical School, University of Tampere, Tampere, Finland. Electronic address: sanna.hagman@uta.fi.
authors.forename: Sanna
authors.initials: S
authors.lastname: Hagman
authors.affiliation: Neuroimmunology Unit, Medical School, University of Tampere, Tampere, Finland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Kolasa
authors.affiliation: Seinäjoki Central Hospital, Department of Neurology, Seinäjoki, Finland.
authors.forename: Keijo
authors.initials: K
authors.lastname: Koivisto
authors.affiliation: Department of Clinical Neurosciences, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Auli
authors.initials: A
authors.lastname: Verkkoniemi-Ahola
authors.affiliation: Department of Clinical Neurosciences, Turku University Hospital, Turku, Finland.
authors.forename: Laura
authors.initials: L
authors.lastname: Airas
authors.affiliation: Neuroimmunology Unit, Medical School, University of Tampere, Tampere, Finland; Department of Neurology, Tampere University Hospital, Tampere, Finland.
authors.forename: Irina
authors.initials: I
authors.lastname: Elovaara
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D056747:Immunomodulation; D016899:Interferon-beta / Q000627:therapeutic use; D007577:JC Virus / Q000276:immunology*; D019041:L-Selectin / Q000097:blood*; D007968:Leukoencephalopathy, Progressive Multifocal; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood / Q000188:drug therapy*; D000069442:Natalizumab / Q000627:therapeutic use*; D012306:Risk; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D015415:Biomarkers; D007155:Immunologic Factors; D000069442:Natalizumab; D019041:L-Selectin; D016899:Interferon-beta
keywords: Anti-JCV antibody index; Biomarkers; Multiple sclerosis; Natalizumab; Progressive multifocal leukoencephalopathy; sL-selectin