Collagen Binding Assay for VWD

1
Collagen Binding Assay for VWD

• The function of von Willebrand Factor has
  traditionally been assessed by the use of the
  ristocetin cofactor assay (VWFRCo). As an
  alternative, a collagen binding ELISA assay
  (VWFCB) may be equally effective and add to
  understanding of the disease.
• The VWFCB assay may be of use as a screening
  tool, primarily because of lower assay
  variability and greater sensitivity to loss of
  high molecular weight multimers.
• The assay is limited by its ability to identify
  and characterize some Von Willebrand Disease
  (VWD) subtypes, primarily type 2M. Because of
  this, it has been generally recommended that the
  VWFCB assay should not replace the ristocetin
  cofactor assay but rather be used in conjunction.

Lab Pointer
Contributed by Elizabeth Plumhoff MT(ASCP), CLS
(NCA) Special Coagulation Laboratory Mayo
Clinic Rochester, Minnesota
www.CLOT-ED.com
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Issues Related to VWFCB Assays

• While animal sources of collagen (equine and
  bovine) do not seem to be critical, type and
  concentration are important. Purified type 1
  collagen is not acceptable whereas either type 3
  or a mixture of types 1 3 are recommended.
• Whole blood specimens maintained at refrigerator
  or room temperature for 24 hours show a loss of
  collagen binding activity. This is due to
  ADAMTS13 activity (protease that cleaves VWF).
• References
• Favaloro EJ, et al. Blood Coagul Fibrinolysis
  19912285-91
• Sadler JE. in Hemostasis and Thrombosis Basic
  Principles and Clinical Practice. RW Colman,
  Editor. Lippincott Williams Wilkins,
  Philadelphia, 4th ED, 2001, pp 825 37
• Casonato A, et al. Br J Haematol 2001112578-83
• Favaloro EJ, et al. Thromb Haemost
  2001861589-90
• Favaloro EJ. Semin Thromb Haemost
  200228191-202
• Turecek PL, et al. Semin Thromb Haemost
  200228149-60

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