Detection of NeuGc-GM3 in cell membrane fraction by slot blot assay in B16 (A and B) and F3II (C and D) cells. A and C, tumor cells were preincubated with different concentrations of NeuGc-rich BSM and processed 24 h later. B and D, tumor cells were preincubated with 250 μg/ml of NeuGc-rich BSM and further processed 24, 48 or 72 h after preincubation. In all cases, densitometric analysis was normalized to the respective control. Means ± SEM of at least 3 determinations are shown. *p < 0.05, **p < 0.01 (ANOVA contrasted with Dunnet test).