SUMMARY, EXPLANATION AND LIMITATIONS:
Factor VIII related antigen or von Willebrand factor is a multimeric glycoprotein, which binds to platelet glycoprotein Ib, glycoprotein IIb/IIIa, collagen and heparin. It is synthesized by endothelial cells and stored in the Weibel-Palade granules. It mediates platelet adhesion to injured vessel walls and serves as a carrier and stabilizer for coagulation factor VIII. Von Willebrand factor is one of the most useful markers to identify endothelial (or megakaryocytic) lineage of neoplasms. As not all endothelial cells synthesize / store) this molecule, about 30% of tumors of vascular origin fail to stain for factor VIII related antigen, regardless of whether they are benign or malignant. Staining for factor VIII related antigen has also been used to measure angiogenesis, an indicator of tumor recurrence.
Immunogen: Partially purified von Willebrand factor from human placenta.
Staining pattern: Cytoplasmic.
Positive control: Tissue sample from tonsil or intestine.
This antibody is designed for the specific localization of human calcitonin using IHC techniques in formalin-fixed, paraffin-embedded tissue sections.
Characterization of endothelial cells or their derivatives in the evaluation of vascularization and inflammatory lesions. Diagnosis of primary or secondary neoplasms of endothelial origin. Analysis of normal and pathological megakaryocytic populations