About Rainbow Scientific

medical diagnostic kits molecular cytogenetics

How to Order clinical chemistry products

Technical Support on molecular cytogenetics and hematology and other medical diagnostic products

Medical Diagnostics Conference Schedule

Contact Rainbow Scientific

Rainbow Scientific logo

 

Products > Life Therapeutics > von Willebrand Assay

von Willebrand Disease

von Willebrand Factor (vWF) is an important blood clotting protein involved in both assisting platelet adhesion and stabilization of clotting factor VIII.

In von Willebrand Disease (vWD), there is either a partial quantitative deficiency or shortage of vWF (classified as vWD Type 1) or a qualitative or functional deficiencey (classified as vWD Type 2). vWD Type 3 is rare and charachterized by virtually complete deficiency of vWF. The incidence of vWD worldwide is estimated at 1% to 3% but may be more common since mild cases may remain undetected.

Historically, a wide variety of assays have been used to characterize vWF. Currently the most common methods are

  • vWF:AG assay by Laurell rocket electrophoreses, ELISA or Latex Immunoassay and
  • Ristocetin Cofactor agglutination (RiCoF) or Ristocetin induced platelet aggregation (RIPA).

These two methods in combination can identify vWD types 1 and 2A which represent some 85% of vWD cases.

Recently, the Collagen Binding Assay (CBA) has been mentioned as a useful alternative to the Ristocetin Cofactor assay for detecting variants of vWF with defective adhesive function. This is an ELISA-like method based on the ability of vWF to bind collagen, which is associated with higher molecular weight multimers of vWF. The CBA assay correlates closely with vWF function and bleeding problems.

von Willebrand Factor Antigen / Collagen Binding Assay

Life Therapeutics have developed a paired ELISA system for the quantitation of von Willebrand Factor antigen (vWF ELISA) and the binding of von Willebrand Factor to collagen type 3 (CBA ELISA).

von Willebrand Factor ELISA assay kit

The vWF ELISA kit is based on vWF in patient plasma binding to antibody coated wells; an antibody conjugate is then introduced to allow chromogenic quantitation of bound vWF.

Collagen Binding Assay Elisa assay kit

The Collagen-Binding Assay was developed to detect variants of vWF with defective adhesive function, based on the ability of vWF in patient plasma to bind to collagen coated on the ELISA plate. This assay provides enhanced discrimination between Type 2 vWD and normal patients, as well as a greater predictive power in confirming vWD Type 2 compared to traditional platelet aggregation assays. Assay variability is marketdly reduced.

VWF/CBA ELISAs are

  • Simple to use
  • Fast - 2hrs 40 minute total
  • Reproducable
  • Less complex and more precise than platelet aggregation methods using ristocetin.
  • Less time consuming than electrophoresis and aggregation methods.

Product Code

VWAE-1 von Willebrand Antigen ELISA kit    1 x 96 well Elisa kit
CBAE-1 Collagen Binding Assay ELISA kit   1 x 96 well Elisa kit


Rainbow Scientific, Inc.
83 Maple Avenue, Windsor, CT 06095
Tel: (860) 298-8382   Fax: (860) 298-8586

email: info@rainbowscientific.com

 

Note: The contents of this web site are for informational purposes only and no further warranties are either expressed or implied. © 2001-2007 Rainbow Scientific, Inc. All rights reserved.

Designed and Hosted by Hosting Connecticut, LLC