There are several macrophage inflammatory proteins (MIP), MIP-1α/CCL3, MIP-1β/CCL4, MIP-1γ/CCL9/10, MIP-1δ/CCL15, MIP-4/CCL18, MIP-3α/CCL19, MIP-3β/CCL20, and MIP-2/CXCL2. With the exception of MIP-2/CXCL2 they are all CC chemokines. In contrast MIP-2/CXCL2 is a CXC chemokine that is a murine functional homolog of CXCL8/IL-8. With the exception of MIP-2/CXCL2 and in common with the other CC chemokines they are all chemotactic for mononuclear leukocytes with varying specificity for particular cell types. In contrast the sole member of the CXC chemokine family, MIP-2/CXCL2, is a potent neutrophil chemoattractant and promotes angiogenesis in vivo. Various members of the MIP family have been implicated in pulmonary host defense and the pathogenesis of pulmonary fibrosis.