TISSUE FACTOR INDUCES MIGRATION OF CULTURED AORTIC SMOOTH-MUSCLE CELLS

Tissue factor (TF) plays a key role as a primary initiator on the extr insic coagulation cascade. Recently, upregulation of TF has been repor ted in human atherosclerotic lesions, We investigated the effects of T F on migration and proliferation of cultured smooth muscle cells (SMCs ) from rabbit aortas. We tested three kinds of recombinant human TF (L -TF: the full length of TF with relipidation, NL-TF: the full length o f TF without relipidation, and S-TF: a soluble form of TF1-219) Only L -TF had coagulant activity, All kinds of TF showed the chemotactic mig ration activity for SMCs. The migration ability of TFs was comparable to those of platelet-derived growth factor (PDGF)-BB and basic fibrobl ast-growth factor (bFGF), and was inhibited by anti-TF polyclonal and monoclonal antibodies. On the other hand, none of the forms of TF indu ced SMC proliferation. These results indicate that TF is not only a co agulation factor but also a strong chemotactic factor for vascular SMC s, and suggest that TF could play an important role in atherogenesis a s well as in hemostasis and thrombosis.