M-DC8⁺ DC-mediated antibody-dependent cytotoxicity toward COLO 205 and SK-BR-3 tumor cells.

(A) Freshly isolated M-DC8⁺ DCs were cocultured in 96-well plates with ⁵¹Cr-labeled COLO 205 cells (5 × 10³ cells/well) in the presence of 17-1A antibody (10 μg/mL), an isotype-matched control antibody (10 μg/mL), or in the absence of antibody, at an effector-target (E/T) ratio of 40:1. After 18 hours of incubation, chromium release was measured. The results of 2 different donors are presented as mean ± SE of triplicate wells. (B) M-DC8⁺ DCs were cocultured in 96-well plates with ⁵¹Cr-labeled SK-BR-3 cells (5 × 10³ cells/well) in the presence of Herceptin antibody (10 μg/mL), an isotype-matched control antibody (10 μg/mL), or in the absence of antibody, at an E/T ratio of 20:1. After 18 hours of incubation, chromium release was measured. The results of 2 different donors are presented as mean ± SE of triplicate wells. (C) ⁵¹Cr-labeled COLO 205 cells (5 × 10³cells/well) were incubated either with M-DC8⁺ DCs, monocytes, or NK cells in the presence or absence of 10 μg/mL 17-1A antibody at different E/T ratios. After 18 hours of incubation, chromium release was determined. Symbols represent means ± SE of results obtained from 4 different donors. For each donor the mean of triplicate determination was taken. (D) ⁵¹Cr-labeled SK-BR-3 cells (5 × 10³ cells/well) were incubated either with M-DC8⁺ DCs, monocytes, or NK cells in the presence or absence of 10 μg/mL Herceptin antibody at different E/T ratios. After 18 hours of incubation, chromium release was determined. Symbols represent means ± SE of results obtained from 4 different donors. For each donor the mean of triplicate determination was taken.