VWF staining on thrombi retrieved from stroke patients. Intracranial thrombi retrieved from stroke patients that underwent thrombectomy procedure were collected for histological analysis. Consecutive thrombi sections were stained with H&E, MSB, and anti-VWF antibodies. For the negative control, primary antibodies were omitted. Classical H&E staining was used to visualize overall thrombus composition and organization. On MSB staining, red areas show the presence of fibrin, whereas red blood cells (RBC) appear yellow. Interestingly, varying amounts of VWF (brown color) were found in all the thrombi analyzed. Two representative patient thrombi are shown illustrating a VWF-rich thrombus (A) and a red blood cell–rich, VWF-poor thrombus (B). Scale bar: 50 μm. (C) Higher magnification showing granular VWF staining. Scale bar: 5 μm. (D) A higher magnification of fibrillar/extracellular VWF. Scale bar: 5 μm. (E) Negative control for the anti-VWF staining. Scale bar: 50 μm.