The urokinase receptor (CD87) facilitates CD11b/CD18-mediated adhesion of human monocytes.

摘要: Urokinase receptors (uPAR; CD87) from complexes with complement receptor 3 (CR3) (CD11b/CD18), a beta2 integrin. In this study, we sought to determine if association modulates the adhesive function of CR3. Both CR3 and uPAR concentrate at ventral surface fibrinogen-adherent human monocytes, CR3-uPAR coupling increases substantially upon adhesion fibrinogen. Pretreatment anti-uPAR monoclonal antibody reduced counterligands (fibrinogen keyhole limpet hemocyanin) by 50%, but did not affect fibronectin, beta1 integrin counterligand. Antisense (AS) oligonucleotides were used selectively suppressing expression also function. AS-uPAR oligo CR3-dependent 43+/-9% (P<0.01), CR3-independent adhesion. To effects are mediated through its ligand, monocytes pre-treated AS block uPA expression. Unlike blocking expression, AS-uPA increased 46% (P<0.005), exogenous intact uPA, fragments, reversed effect. We conclude that complex formation facilitates functions This is dependent occupancy which negatively influences