title: The level of serum visfatin (PBEF) is associated with total number of B cells in patients with rheumatoid arthritis and decreases following B cell depletion therapy.
abstract: OBJECTIVE
  Visfatin, also known as pre-B cell colony-enhancing factor, was recently characterized as a potent pro-inflammatory mediator in rheumatoid arthritis (RA). The aim of this study was to determine the effect of B cell depletion with rituximab on serum visfatin levels in patients with active RA.
  
  
  METHODS
  We evaluated 31 patients with RA starting rituximab therapy at baseline and after 16 and 24 weeks using disease activity score (DAS28). The control group consisted of 33 gender and age-matched healthy individuals. CD19(+) B cells were assessed by flow cytometry and serum levels of visfatin and B cell-activating factor of the TNF family (BAFF) were measured by ELISA at baseline and week 16.
  
  
  RESULTS
  Total number of B cells correlated positively with serum visfatin levels (rs=0.417, P=0.025) and negatively with serum BAFF levels (rs=-0.486, P=0.008) at baseline. Serum visfatin levels were significantly higher in patients with RA compared with healthy controls (P=0.026), and significantly decreased (P=0.010), while BAFF increased (P<0.001), and both proteins became negatively correlated following treatment with rituximab (rs=-0.438, P=0.017). Visfatin levels did not correlate with the disease activity, but lack of change in the serum visfatin levels between baseline and week 16 predicted worsening disease activity between weeks 16 and 24 (rs=0.452, P=0.014).
  
  
  CONCLUSIONS
  In patients with active RA, serum visfatin levels are related to the number of B cells rather than to disease activity and decrease in response to treatment with rituximab. Further studies are necessary to show if visfatin is a marker with predictive value for deterioration of RA.
authors.affiliation: Institute of Rheumatology, Department of Experimental and Clinical Rheumatology, First Faculty of Medicine, Charles University in Prague, Czech Republic. seno@revma.cz
authors.forename: Ladislav
authors.initials: L
authors.lastname: Senolt
authors.forename: Olga
authors.initials: O
authors.lastname: Kryštůfková
authors.forename: Hana
authors.initials: H
authors.lastname: Hulejová
authors.forename: Markéta
authors.initials: M
authors.lastname: Kuklová
authors.forename: Mária
authors.initials: M
authors.lastname: Filková
authors.forename: Lucie Andrés
authors.initials: LA
authors.lastname: Cerezo
authors.forename: Jaromír
authors.initials: J
authors.lastname: Běláček
authors.forename: Martin
authors.initials: M
authors.lastname: Haluzík
authors.forename: Sárka
authors.initials: S
authors.lastname: Forejtová
authors.forename: Steffen
authors.initials: S
authors.lastname: Gay
authors.forename: Karel
authors.initials: K
authors.lastname: Pavelka
authors.forename: Jiří
authors.initials: J
authors.lastname: Vencovský
mesh_terms: D058846:Antibodies, Monoclonal, Murine-Derived / Q000494:pharmacology / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000188:drug therapy / Q000276:immunology*; D053264:B-Cell Activating Factor / Q000378:metabolism; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D003710:Demography; D018450:Disease Progression; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion; D008297:Male; D008875:Middle Aged; D054409:Nicotinamide Phosphoribosyltransferase / Q000097:blood*; D011237:Predictive Value of Tests; D000069283:Rituximab
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D053264:B-Cell Activating Factor; C505719:TNFSF13B protein, human; D000069283:Rituximab; D054409:Nicotinamide Phosphoribosyltransferase