HIV-1_BaL p24⁺ DCs produce TNFα but fail to produce IL-12 p70 in response to CD40L stimulation. Immature DCs and control DCs were exposed to 10 × HIV-1_BaL for 72 hours with or without CD40L stimulation for the final 6 hours (TNFα) or 24 hours (IL-12 p70). As an additional control, the HIV-1_BaL was washed off after overnight incubation and the DCs were cultured for 72 hours with or without CD40L stimulation for the final 6 hours (TNFα) or 24 hours (IL-12 p70). The figure shows intracellular cytokine production in p24^- and p24⁺ DCs and control DCs after no stimulation (medium), HIV-1_BaL exposure 72 hours (10× BaL), HIV-1_BaL exposure overnight and cultured for 72 hours (10 × BaL washed off), CD40L stimulation alone, or HIV-1_BaL exposure followed by CD40L stimulation. Gates were set on large CD1a⁺ CD3^- cells. Numbers indicate frequency of stained DCs.