Chemokines are low molecular weight secretory proteins that function principally as stimulators of leukocyte recruitment. There are four defined chemokine subfamilies based on their primary structure, CXC, CC, C and CX3C. Members of the CC chemokine subfamily, a such as monocyte chemoattractant protein 1 (MCP-1) are chemotactic for monocytes and other leukocyte subsets. Because monocytes produce factors that regulate bone formation or resorption, such as PDGF, IL-1 or TNF, chemokines that initiate their recruitment are likely to be important in regulating osseous metabolism. In the studies below, data is presented demonstrating mechanisms of MCP-1 expression in osteoblastic cells. These studies establish that MCP-1 is induced during osseous inflammation and in developmentally regulated bone remodelling, and is associated with enhanced monocyte recruitment when applied to osseous lesions.