In vivo depletion of complement. Mice were treated with a single dose of CVF or HC3-1496 (n = 3 mice per group), and serum was harvested and evaluated for complement activity. Changes in CH50 from baseline were evaluated (A). Serum obtained at 6 hours was evaluated for its ability to inhibit activation of NK cells by mAb-coated target cells as indicated by up-regulation of CD54 (B). Error bars represent SD of the mean.