Inhibitory Effects of TSG-6 Link Module on Leukocyte–Endothelial Cell Interactions In Vitro and In Vivo

Authors

  • THONG V. CAO,

    1. The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, London, UK
    Search for more papers by this author
  • MYLINH LA,

    1. The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, London, UK
    Search for more papers by this author
  • STEPHEN J. GETTING,

    1. The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, London, UK
    Search for more papers by this author
  • ANTHONY J. DAY,

    1. MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford, UK
    Search for more papers by this author
  • MAURO PERRETTI

    Corresponding author
    1. The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, London, UK
      Address correspondence to Mauro Perretti, The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK. E-mail: M.Perretti@qmul.ac.uk
    Search for more papers by this author

  • This work was supported by the British Heart Foundation (PG/2000022). MP is a senior fellow of the Arthritis Research Campaign UK.

Address correspondence to Mauro Perretti, The William Harvey Research Institute, Bart's and the London Queen Mary School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK. E-mail: M.Perretti@qmul.ac.uk

ABSTRACT

Objective: The authors investigated whether the anti-inflammatory protein tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6) and its Link module (Link_TSG6) could affect the complex multistep process of leukocyte/endothelial cell (EC) interaction.

Methods: Mouse mesenteries were inflamed with interleukin (IL)-1β and the extent of leukocyte rolling, adhesion, and emigration was determined after 2 h. Link_TSG6 and a single-point mutant (termed K13E) were given intraperitoneally together with the cytokine. Human neutrophil chemotaxis and transmigration were determined in vitro in response to IL-8 and/or TNF-α. TSG-6, Link_TSG6, and K13E were added to the leukocytes or the EC monolayers.

Results: Co-injection of Link_TSG6 with IL-1β selectively inhibited cell flux, adhesion, and emigration as analyzed in mesenteric postcapillary venules. The fewer cells that rolled in the animals treated with Link_TSG6 displayed a velocity similar to that measured in vehicle-treated mice. In vitro, Link_TSG6 did not affect neutrophil chemotaxis or EC activation but did inhibit neutrophil transmigration across EC monolayers. The latter effect was shared by full-length TSG-6 and observed equally in response to IL-8 or TNF-α.

Conclusions: These data restrict the site of action for at least some of the anti-inflammatory effects ascribed to TSG-6/Link_TSG6 to the microenvironment of the extravasating leukocyte.

Ancillary