FIG 4.
Complement-enhanced Fc variants of IgG1 b12 do not mediate viral lysis despite detectable deposition activity on viral particles. Antibodies were assayed for their ability to bind to the surface of HIV-1BaL particles bound to lectin-conjugated magnetic beads (A), recruit C1q to the viral surface (B), and affect terminal complement activities, including C3 deposition (C), C5b-9 complex formation (D), and MAC-mediated lysis (E), determined by the detection of released capsid protein p24. Dotted lines represent average baseline complement deposition on beads in wells containing a nonspecific isotype control (A to D) or antibody-independent baseline complement deposition and heat-inactivated NHS (E). Points and error bars represent means ± standard deviations from technical triplicates, respectively. Data are reported as mean or median fluorescence intensities (mFI or MFI, respectively) and are representative of results from two independent experiments. huIgG, human IgG.