title: Monocyte migration to the synovium in rheumatoid arthritis patients treated with adalimumab.
abstract: OBJECTIVE
  The mechanism of action of treatment with tumour necrosis factor (TNF) blockers in rheumatoid arthritis (RA) is still not completely understood. The aim of this study was to test if adalimumab treatment could affect the influx of monocytes into the synovium.
  
  
  METHODS
  A novel technique was used to analyse the migration of labelled autologous monocytes before and 14 days after initiation of adalimumab treatment using scintigraphy. CD14 monocytes were isolated from patients with RA, using a positive selection procedure with magnetic-activated cell sorting, and labelled with technetium-99m-hexamethylpropylene-amino-oxime. Scintigraphic scans were made 1, 2 and 3 h after re-infusion.
  
  
  RESULTS
  As early as 14 days after the start of treatment with adalimumab a significant decrease in disease activity score evaluated in 28 joints was shown. There was no significant decrease in the influx of monocytes into the joint at this time.
  
  
  CONCLUSIONS
  This study indicates that adalimumab treatment does not reduce the influx of monocytes into the synovium early after initiation of treatment. As previous studies showed a rapid decrease in macrophage infiltration after TNF-antibody therapy, which could not be explained by increased cell death, this points to an important role for enhanced efflux of inflammatory cells from the synovium.
authors.affiliation: D ivision of Clinical Immunology and Rheumatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: M M J
authors.initials: MM
authors.lastname: Herenius
authors.forename: R M
authors.initials: RM
authors.lastname: Thurlings
authors.forename: C A
authors.initials: CA
authors.lastname: Wijbrandts
authors.forename: R J
authors.initials: RJ
authors.lastname: Bennink
authors.forename: S E
authors.initials: SE
authors.lastname: Dohmen
authors.forename: C
authors.initials: C
authors.lastname: Voermans
authors.forename: D
authors.initials: D
authors.lastname: Wouters
authors.forename: E S
authors.initials: ES
authors.lastname: Izmailova
authors.forename: D M
authors.initials: DM
authors.lastname: Gerlag
authors.forename: B L F
authors.initials: BL
authors.lastname: van Eck-Smit
authors.forename: P P
authors.initials: PP
authors.lastname: Tak
mesh_terms: D000068879:Adalimumab; D000911:Antibodies, Monoclonal / Q000494:pharmacology* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000473:pathology; D002465:Cell Movement / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects* / Q000502:physiology; D012720:Severity of Illness Index; D013583:Synovial Membrane / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha; D000068879:Adalimumab