Figure 2.

Stem cell mobilization.

†G-SCF causes stem cell mobilization through direct plasminogen-mediated downregulation of SDF-1 and MMP-9 dependent release of SCF. ‡Tissue and urinary plasminogen activators promote MMP-9 mediated release of SCF and decrease SDF-1 levels in the bone marrow. ◊SDF-1 and VEGF stimulate release of pro-MMP-9 which results in increased SCF and stem cell mobilization. *Aprotinin is a plasminogen inhibitor which consequently inhibits MMP-9 activation and stem cell mobilization. G-CSF: Granulocyte colony-stimulating factor; MMP-9: matrix metalloproteinase 9; SCF: stem cell factor; SDF-1: stromal cell-derived factor 1; t-PA: tissue-type plasminogen activator; u-PA: urinary-type plasminogen activator; VEGF: vascular endothelial growth factor.