Fig. 3

2B4 and 1D12 inhibit cancer adhesion in vitro and metastasis in vivo. a 2B4 and 1D12 inhibited platelet, LLC cell, and endothelial cell adhesion between each other. Effect of 2B4 (blue) and 1D12 (orange) on the adhesion of LLC with BCECF-labeled platelet (Left panel), mouse BCECF-labeled platelets with HUVECs (middle panel), and BCECF-labeled LLC cells with HUVECs (right panel) in vitro. The negative control was in the form of rat IgG (gray). b 2B4 and 1D12 inhibited adhesion of LLC to mouse platelets from mice with pulmonary metastasis. Washed mouse platelets were divided from tumor-bearing mouse blood and healthy mouse blood. The adhesion of LLC with BCECF-labeled platelet was detected with a fluorescence plate reader and observed under a fluorescence microscope. The negative control is in the form of rat IgG or rat Fab. Average fluorescence intensity was shown in right graphs (± SD, P value is indicated; *P < 0.05; **P < 0.01; ***P < 0.001). c, d Pulmonary metastasis was assessed after B16F10 and LLC injection with control IgG (50 μg/mouse), 2B4 (50 μg/mouse), 1D12 (50 μg/mouse), control Fab (50 μg/mouse), 2B4 Fab (50 μg/mouse), or 1D12 Fab (50 μg/mouse) through the lateral tail vein (n = 4 mice in each group). Metastasis was analyzed 14 days after injection of tumor cells. Representative examples of the lungs (one of each group) with metastatic foci were depicted. Average number of lung metastasis in each of the groups was shown in right graphs (± SD, P value is indicated; *P < 0.05; **P < 0.01; ***P < 0.001). e Representative histologic evidence from tumor sections of the different groups. Four percent of paraformaldehyde-embedded lungs of all mice were cut completely, stained with hematoxylin and eosin, and examined histologically. Representative sections of two mice from 2B4 groups, 1D12 groups, and control IgG groups were shown. Each figure is a representative of three independent experiments