Role of Plasmin and uPAR in Bone Marrow HSC/HPC Retention and Mobilization.

We previously identified the plasmin protease family as a critical determinant of the mobilization of hematopoietic stem and progenitor cells (HSC/HPC), but the role of the urokinase receptor uPAR remained unclear. uPAR is a membrane-anchored glycoprotein, which not only localizes its ligand urokinase (uPA) to the cell surface via its GPI-anchor but also regulates β1-integrin dependent cell adhesion and migration.