MMP9 and graft versus host disease: Mice given 1 × 106 MDSCs showed lower serum levels of C reactive protein (CRP), IL-1β, IL-6, TNF-α, IL-17, macrophage inflammatory protein-3β (MIP-3β), matrix metallopeptidase 9 (MMP9), Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES) and stromal cell-derived factor-1α (SDF-1α) compared to control GVHD mice.