Macrophage inflammatory protein 1 beta (MIP-1β), also known as Chemokine (C-C motif) ligand 4(CCL4), is a small cytokine belonging to the CC chemokine family. It is a chemoattractant for natural killer cells, monocytes and a variety of other immune cells. MIP-1βis a major HIV-suppressive factor produced by CD8+ T cells. Perforin-low memory CD8+ T cells are the most common T-cells that normally synthesize MIP-1-beta in humans. MIP-1βhas been shown to interact with CCL3. It can signal through the CCR5 receptor.
Recombinant MIP-1 beta/CCL4 produced in E. coli is a single non-glycosylated polypeptide chain containing 69 amino acids. A fully biologically active molecule, rhMIP-1 beta/CCL4 has a molecular mass of 7.6 kDa analyzed by reducing SDS-PAGE and is obtained by chromatographic techniques at ExCell Bio.