HIV activation by TNFα and TSA in ACH-2, U1, and J1.1 latently infected cell lines with or without Aza-CdR. A. p24 antigen production in ACH-2, U1 and J1.1 cell lines for all treatments and treatment combinations at 48 h post-induction. Cells were cultured in RPMI with 10% FBS. 2 million cells were treated with the different compounds for 48 h. The compound order of addition was determined in Fig. 1. After 48 h, cells were pelleted at 1400 rpm for 7 min and discarded. Supernatants from the different treatment conditions were stored at -80°C until further use. p24 antigen was determined using ELISA (Perkin Elmer, Waltham, MA) from the stored supernatants. B. Cell viability of the different treatments and treatment combinations shown in panel A, determined with an MTS assay (Promega, Madison, WI) at 48 h post-treatment. Compound final concentrations of the activators were Aza-CdR (2.5 μM), TNFα (10 ng/ml) and TSA (1.5 μM). Results are the mean ± standard deviation (SD). Statistical analysis (Student's t-test) was performed using STATA software package (StataCorp LP, College Station, TX), * p ≤ 0.05.