title: Takayasu arteritis is characterised by disturbances of B cell homeostasis and responds to B cell depletion therapy with rituximab.
abstract: Introduction Takayasu arteritis (TA) is a large vessel vasculitis involving the aorta and its major branches. T cell-mediated autoimmunity is thought to play a major role in its pathogenesis, while the role of B cells is still unclear.
  
  
  METHODS
  B cell subsets in the peripheral blood of 17 patients with TA were analysed and compared with nine patients with active systemic lupus erythematosus (SLE) and nine healthy controls by flow cytometry. Based on these findings, three patients with active refractory TA were treated with B cell depletion therapy (BCDT) using monoclonal anti-CD20 antibodies (rituximab).
  
  
  RESULTS
  The absolute number and frequency of peripheral blood CD19(+)/CD20(-)/CD27(high) antibody-secreting cells in patients with active TA was significantly higher than in healthy donors. As in active SLE, the majority of these cells are newly generated plasmablasts which significantly correlated with TA activity. Three patients with active refractory TA and expansion of plasmablasts were successfully treated with BCDT, which resulted in remission.
  
  
  CONCLUSIONS
  Disturbances of B cell homeostasis may be critical in TA. Circulating plasmablasts could be a useful biomarker of disease activity and a tool for selecting appropriate candidates for BCDT. B cells and plasmablasts/plasma cells may therefore represent novel targets for effective therapies for TA.
authors.affiliation: Department of Medicine (Clinic for Rheumatology and Clinical Immunology), Charité- Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Bimba F
authors.initials: BF
authors.lastname: Hoyer
authors.forename: Imtiaz M
authors.initials: IM
authors.lastname: Mumtaz
authors.forename: Konstanze
authors.initials: K
authors.lastname: Loddenkemper
authors.forename: Anne
authors.initials: A
authors.lastname: Bruns
authors.forename: Claudia
authors.initials: C
authors.lastname: Sengler
authors.forename: Kay-Geert
authors.initials: KG
authors.lastname: Hermann
authors.forename: Sofiane
authors.initials: S
authors.lastname: Maza
authors.forename: Rolf
authors.initials: R
authors.lastname: Keitzer
authors.forename: Gerd-Rüdiger
authors.initials: GR
authors.lastname: Burmester
authors.forename: Frank
authors.initials: F
authors.lastname: Buttgereit
authors.forename: Andreas
authors.initials: A
authors.lastname: Radbruch
authors.forename: Falk
authors.initials: F
authors.lastname: Hiepe
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D058846:Antibodies, Monoclonal, Murine-Derived / Q000627:therapeutic use*; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D004341:Drug Evaluation; D005260:Female; D006706:Homeostasis / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion / Q000379:methods*; D008297:Male; D008875:Middle Aged; D000069283:Rituximab; D012720:Severity of Illness Index; D013625:Takayasu Arteritis / Q000188:drug therapy* / Q000276:immunology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D007166:Immunosuppressive Agents; D000069283:Rituximab