Macrophage Inflammatory Protein-1 alpha (MIP-1 alpha), which is also known as CCL3, is a member of the beta (C-C) subfamily of chemokines. MIP-1 alpha is a monocyte chemoattractant. Reports have also demonstrated chemoattractant and adhesive effects by MIP-1 alpha on CD8 T cells, B cells, and eosinophils. MIP-1 alpha has been identified as a stem cell inhibitory factor that can block the proliferation of hematopoietic stem cells. Recombinant Human MIP-1 alpha produced in E.coli is a single polypeptide containing 70 amino acids and with a molecular mass of 7.8 kDa.