Modulation of granulocyte-endothelium interactions by antileukoproteinase: inhibition of anti-type II collagen antibody-induced leukocyte attachment to the synovial endothelium

Arthritis Res Ther. 2006;8(4):R95. doi: 10.1186/ar1973.


Antileukoproteinase (ALP) is a physiological inhibitor of granulocytic serine proteases that has been shown to have anti-inflammatory properties in addition to its antiproteolytic activity. On the basis of its potential to block anti-collagen type II (CII) antibody-induced arthritis (CAIA) and to suppress the conformational activation of beta2-integrins in leukocytes, the present study was undertaken to investigate its interference with leukocyte adherence to cytokine-activated endothelium. The potential of recombinant ALP to block the interactions of leukocytes with the endothelial lining was concomitantly investigated in vitro and in vivo. Thus, intravital fluorescence microscopic imaging of leukocyte rolling and firm adhesion to postcapillary venules were performed in the knee joints of DBA1/J mice after intravenous injection of anti-CII mAbs. An IL-1beta-activated endothelial layer formed by a murine glomerular cell line (glEND.2) was used to assay the interaction with human leukocytes in vitro. Electromobility shift and luciferase reporter gene assays permitted the analysis of cytokine-induced activation of the NF-kappaB pathway. Fluorescence-activated cell sorting was applied to determine endothelial E-selectin expression. Leukocyte rolling and firm adhesion to the synovial endothelium in an early response to the anti-CII antibody transfer were significantly decreased in ALP-pretreated mice. Concomitantly, ALP suppressed the IL-1beta-induced NF-kappaB activation and the upregulation of E-selectin expression in glEND.2 cells in vitro. These findings support the notion that the newly uncovered properties of ALP to interfere with cytokine signalling and upregulation of adhesion molecules in endothelial cells are likely to contribute to the therapeutic potential of ALP in immune-complex-induced tissue injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / pharmacology*
  • Cell Adhesion / drug effects
  • Cell Communication / drug effects*
  • Cell Line
  • Cell Separation
  • Collagen Type II / immunology*
  • E-Selectin / metabolism
  • Endothelial Cells / metabolism
  • Endothelial Cells / physiology
  • Flow Cytometry
  • Granulocytes / physiology*
  • Humans
  • Interleukin-1beta / pharmacology
  • Knee Joint / blood supply
  • Leukocyte Rolling / drug effects
  • Leukocytes / physiology*
  • Mice
  • Mice, Inbred DBA
  • Microscopy, Fluorescence
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / metabolism
  • Recombinant Proteins / pharmacology
  • Secretory Leukocyte Peptidase Inhibitor / pharmacology*
  • Synovial Membrane / blood supply
  • Synovial Membrane / metabolism
  • Synovial Membrane / physiology*
  • Up-Regulation / drug effects
  • Venules / physiology


  • Antibodies, Monoclonal
  • Collagen Type II
  • E-Selectin
  • Interleukin-1beta
  • NF-kappa B
  • Recombinant Proteins
  • Secretory Leukocyte Peptidase Inhibitor