Fig. 5.

C5A blocks an ongoing HIV infection. (a) Primary CD4⁺ T lymphocytes (0.5 × 10⁶ cells) were exposed to NL4.3-BaL (1 ng of p24) for 1 day at 37°C and washed. Three days after infection, C5A or control peptide (5 μM) was added to infected cells for 2 h and washed. Infected cell culture supernatants were collected every 3 days, normalized for particulate p24 content, and tested for infectivity (1 ng of p24) on TZM reporter cells. Error bars represent standard errors of duplicates. (b) 293T cells (1 × 10⁶ cells) transfected with 1 μg of proviral NL4.3 or NL4.3-BaL DNA for 24 h at 37°C were treated with or without C5A or control peptide (5 μM) for 1 h at 37°C and washed. Twenty-four hours after peptide treatment, supernatants of transfected 293T cells containing newly formed viruses were tested for infectivity as described in a. Error bars represent standard errors of duplicates.