Expression of MCP-1 mRNA in MDM after HIV infection. MDM were infected with HIV-1 BaL (MOI: 0.1). Total RNA was extracted and MCP-1 expression was measured by RT-PCR at the indicated days postinfection. On normalization against GAPDH and given the arbitrary value of 1 to the MCP-1 mRNA of uninfected cultures after densitometric scanning (Molecular Dynamics, Sunnyvale, CA), RNA induction levels in HIV-infected MDM were 1.4 at day 5 and 12.4 at day 10, respectively. The results are representative of three independent experiments.