CXCL8 and infection: Similarly, infections with R. rickettsii, R. conorii, and R. africae caused the secretion of two chemokines, IL-8 and monocyte chemoattractant protein 1 (MCP-1, also known as CCL2) from endothelial cells, implying their roles in activating and recruiting neutrophils and monocytes to the sites of infection (75, 77, –, 79).