Fig. 3

Continuous presence of intravascular and firmly adherent platelets in AT-3 mammary tumors and B16F1 melanoma. AT-3 or B16F1 cells were injected subcutaneously in the dorsal skin and allowed to grow for 5 to 7 days before surgical implantation of a dorsal skinfold chamber. Representative intravital images of the microcirculation of B16F1 and AT-3 tumors in mice injected with FITC-dextran and fluorescent antibodies to GPIX, fibrin, Gr-1, or PECAM-1, as indicated. White arrow indicates individual platelets adhering firmly to tumor vessels. The asterisk indicates a platelet-fibrin deposit. The white arrowhead shows a platelet-neutrophil complex adhering to tumor vessels. Bar = 10μm