Fractalkine, a CX3C‐chemokine, functions predominantly as an adhesion molecule in monocytic cell line THP‐1

Publisher Website
Google Scholar
Abstract
A newly identified CX3C‐chemokine, fractalkine, expressed on activated endothelial cells plays an important role in leucocyte adhesion and migration. Co‐immobilized fractalkine with fibronectin or intercellular adhesion molecule‐1 enhanced adhesion of THP‐1 cells, which express the fractalkine receptor (CX3CR1), compared with that observed for each alone. That adherence was fractalkine‐dependent and was confirmed in blocking studies. However, soluble fractalkine induced little chemotaxis in THP‐1 cells in comparison to monocyte chemotactic protein‐1 (MCP‐1), which induced a strong chemotactic response. Moreover, the membrane form of fractalkine expressed on ECV304 cells reduced MCP‐1 mediated chemotaxis of THP‐1 cells. These results indicate that fractalkine may function as an adhesion molecule between monocytes and endothelial cells rather than as a chemotactic factor.
Funding Information
  • Japanese Ministry of Education, Science and Culture and the Science Research (09671940, 11470464, 12470401)
  • Japan Private School Promotion Foundation
  • Osaka Dental University Research Foundation