von Willebrand factor (vWF)

Reviewer: Nat Pernick, M.D. (see Reviewers page)
Revised: 29 October 2015, last major update June 2005
Copyright: (c) 2003-2015,, Inc.
Definition / General
  • Large glycoprotein involved in platelet aggression and adhesion to subendothelial matrix
  • Somewhat sensitive (50-75%) for vascular tumors; CD31, CD34 or perhaps FLI1 are more sensitive
  • Cytoplasmic stain
  • Endothelium should be a positive internal control
Positive Staining - Normal
  • Endothelial cells, megakaryocytes, subendothelial connective matrix
  • Areas of tumor necrosis and hemorrhage
Positive Staining - Disease
  • Blood vessels in tumors, vascular tumors, metastatic osteosarcoma
Micro Images

Image hosted on other servers:

Positive staining of endothelium (fig 2A)

Additional References