CCL8 and acute monocytic leukemia: To make sure whether MCP-2/CCL8 could be induced by mycobacteria in human macrophages, we then infected phorbol-12-myristate-13-acetate (PMA)-differentiated THP1, a human acute monocytic leukemia cell line, with either BCG or H37Rv respectively at MOI 5 for 24 h and 48 h, and analyzed the production of MCP-2/CCL8 by ELISA.