MIP-1α plays an important role in the development and regulation and recruitment of leukocytes. CCL3 is produced by a variety of cells, including lymphocytes, fibroblasts, and epithelial cells, as well as both resident and recruited monocytes macrophages. CCL3 has roles in the compartmentalization and mobilization of myeloid precursor cells (MPCs).

Through the use of CCR1 knockout mice, CCL3 has been shown to mediate the mobilization of MPCs from the bone marrow, as well as having regulatory effects on MPCs and acting to stimulate mature MPCs, but CCL3 inhibits immature cells. CCL3 has been reported to be chemotactic for both neutrophils and monocytes in vitro and in vivo in mice. In humans and higher primates, however, predominantly monocytic cellular infiltrates will accumulate in response to direct injection of CCL3.