Epidermal Growth Factor Receptor as Target for Perioperative Elimination of Circulating Colorectal Cancer Cells

Figure 5

Incubation of tumor cells with plasma from cetuximab-treated patients and subsequent ADCP by macrophages. (a) A431, (b) HCT116, (c) HT29, and (d) SW948 cells were incubated with diluted plasma from cetuximab-treated patients. Dilutions ranged from 10% to 0.078%. 10% plasma that had been obtained prior to treatment was used as the negative control. Binding of cetuximab was determined with flow cytometry. Titration curves of plasma from five different patients are shown. MFI = mean fluorescence intensity. (e) Human monocyte-derived macrophages were incubated with A431 cells in the presence of 0.1% plasma from patients pre- and postcetuximab infusion. Tumor cell killing was analyzed by flow cytometry. The percentage killing shown is relative to the no plasma control. Bars represent mean ± SEM. .

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