Von Willebrand Factor VIII
Expected Turnaround Time
2 days
Stated turn-around-times (TATs) are for clinical use only and subject to change based on biopharma protocol requirements. Final TATs will be specified in the biopharma study contract.
Stated turn-around-times (TATs) are for clinical use only and subject to change based on biopharma protocol requirements. Final TATs will be specified in the biopharma study contract.
Clinical Information
The von Willebrand factor (VWF) is a glycoprotein involved in platelet adhesion and aggregation, and it plays a critical role in hemostasis by stabilizing factor VIII in the blood clotting process. In pathology, vWF is used to assess vascular endothelium and to diagnose bleeding disorders like von Willebrand disease. Additionally, vWF is helpful in identifying endothelial tumors, such as hemangiomas and angiosarcomas.
Requisition Forms
Specimen Requirements
Specimen Requirements
- Fresh Tissues: Fixative should be at a 20:1 fixative to tissue ratio, 10% neutral buffered formalin (NBF) for 6-72 hours (48-72 hours PREFERRED)
- Formalin-fixed Paraffin Embedded Tissue (FFPE blocks): FFPE Block, Formalin Fixed
- Unstained slides: 2 slides (3-5 μM) per stain (min 1 slide per stain), Formalin Fixed
Specimen Stability
- Fresh Tissue Tissues: ≤ 72 Hours
- Formalin-fixed Paraffin Embedded Tissue (FFPE blocks): Indefinite
- Unstained slides: Indefinite
Storage Requirements
15°C to 25°C
Shipping Conditions
Ambient
Shipping Recommendations
- Fresh Tissues: AMBIENT
- Formalin-fixed Paraffin Embedded Tissue (FFPE blocks) and unstained slides: AMBIENT, Use a refrigerated (NOT FROZEN) gel pack in the shipment to protect from extreme temperatures. Separate gel pack from specimen.
- Specimens may be transferred to 70% alcohol for transportation purposes after fixation in 10% NBF or B plus.
Specimen Rejection Criteria
Specimens must be fixed in 10% NBF or B plus. All other fixatives will be rejected.
Test Details
Synonyms
Factor VIII Related Antigen, Coagulation Factor VIII VWF, vWF
Test Method
Immunohistochemistry
Methodology Category
IHC
Regulatory Status
IVD, CE-marked
Special Considerations
- Fresh Tissues: Specimens may be fixed in formalin for 24-72 hours by collection sites, then transferred to 70% ethanol and stored at 2-8°C for longer term storage if needed. Samples must be tested 3 months after placing in ethanol.
- Unstained slides: Positively charged glass slides required to prevent background staining and prevent tissue loss. Slides should be left unbaked.