HIV-1 virions produced via PI-mediated activation of latent virus exhibit reduced infectivity. A. OM-10.1 cells were treated with 50 ng/ml TNFα to stimulate the production of positive control viral particles, with 5 μM CLBL to stimulate the production of viral particles under the influence of proteasome inhibition or with DMSO as a negative control. Seventy-two hours post-treatment, viral supernatants were collected and p24 levels were analyzed via p24 ELISA. Values shown represent p24 levels (ng/mL) calculated using standard curve values. B. CLBL and TNFα treated virus-containing supernatants were diluted to a p24 concentration of 200 ng/ml and used to infect U373-MAGI-CXCR4CEM cells. Forty-eight hours post-infection, β-Gal expression was quantified using the β-Gal Enzyme Assay System (Promega, Madison, WI) and standard curve values. Numbers depict β-Gal expression normalized to protein concentrations. Error bars indicate SEM. Asterisks indicate a significant difference (p<0.01) in β-Gal expression between cells infected with TNFα treated virus and CLBL treated virus. P-value was calculated using one-tailed Student’s t test. Results represent average values from three independent experiments.