Fig. 7.
Deposition of rat C3 on MCF7 cells following incubation in NK cell culture supernatant.
Culture supernatant derived from cultured rat NK cells in the presence of immobilized anti–MCF7 antibodies was removed at time 0 (A) 4 hours (B) and 12 hours (C) and incubated with MCF7 cells opsonized with complement activating anti–MCF7 antibody. Deposition of C3 on MCF7 cells was detected by flow cytometry after staining with anti–rat C3. For a positive control, antibody-coated MCF7 cells were incubated in 10% C6-deficient rat serum (D). Experiments were performed using cell concentrations and culture conditions that were used for cytoxicity assays. Histograms with relative mean fluorescence values are shown from a representative experiment of 2.