MIP-1α (macrophage inflammatory protein-1α is a 60-amino acid CC chemokine with a molecular weight of 7.9 kDa. MIP-1α induces migration of monocytes/macrophages, B-lymphocytes, activated CD8+ T cells, natural killer (NK) cells, eosinophils. MIP-1α also stimulates basophils to release histamine, induces ICAM-1 expression, mast cell degranulation, and production of TNF-α, IL-1 and IL-6. In addition to its proinflammatory activities, MIP-1α inhibits the proliferation of hematopoietic stem cells in vitro and in vivo.