Fig. 3

The podoplanin-CLEC-2 interaction increases platelet and melanoma tumour cell aggregation in vitro. PDPN + and PDPN- B16-F0 cells were mixed with platelets from WT or CLEC-2 KO mice in vitro to observe the interaction between the tumour cells and platelets. (A). Flow cytometry profiles of platelets from WT and CLEC-2 KO mice mixed with PDPN + or PDPN- B16-F0 tumour cells. The mean fluorescence intensity (MFI) of each group is shown. The MFI of platelets without CellTracker labelling was used as a control. (B). Fold changes in mean fluorescence intensity compared with the control (unlabelled WT platelets mixed with PDPN + cells) were determined. Data are means ± SEMs (n = 3). (**P < 0.01) (C). Representative immunofluorescence images of tumour cells mixed with platelets in vitro. WT platelets mixed with PDPN + cells induced platelet and tumour cell aggregation. Scale bar = 10 μm. (D). The numbers of tumour cells associated with platelets were quantified by evaluating sections. At least 6 independent images for each sample were analysed. Data are means ± SEMs. (****P < 0.0001)