| Here , we show that LRP1B , a member of LRs , modulates the migration of smooth muscle cells ( SMCs ) by increasing the degradation of membrane receptors , urokinase type plasminogen activator receptor ( uPAR ) , and platelet derived growth factor receptor ( PDGFR ) beta . ^^^ Cell surface and internalization assays , in combination with coimmunoprecipitation experiments , showed that LRP1B binds and internalizes uPAR . ^^^ Metabolic labeling analysis demonstrated that anti LRP1B IgY decreased the catabolism of uPAR . ^^^ CONCLUSIONS : LRP1B modulates the catabolism of uPAR and PDGFR , affecting the migration of SMCs . ^^^ |