Antibodies (IMAGE) Rice University Caption At 100X magnification, this optical microscope image reveals fluorescently tagged antibodies that are bound to clotting factor VIII (red) and von Willebrand factor (VWF) (green) inside organelles known as Weibel-Palade bodies in human umbilical vein endothelial cells. Yellow areas contain roughly equal amounts of factor VIII and VWF. Credit N. Turner/Rice University Usage Restrictions Must credit: "N. Turner/Rice University" License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.