Here is a summary of our July, 2012 Quick Question:
How do you assay for von Willebrand factor (VWF) activity?
a. VWF ristocetin cofactor (VWF:RCo) by aggregometry: 21 (34%)
b. Automated VWF ristocetin cofactor (VWFRCo): 21 (34%)
c. VWF activity immunoassay (VWF:Act): 15 (25%)
d. Collagen binding assay (CBA): 4 (7%)
It seems the collagen binding assay (CBA), despite slightly superior reproducibility compared to the VWF activity immunoassay (Favaloro), has not caught on. It would be interesting to learn whether anyone is currently validating or planning to adopt the CBA.
Favaloro EJ, Bonar R, Chapman K, Meiring M, Funk Adcock D. Differential sensitivity of von Willebrand factor (VWF) ‘activity’ assays to large and small VWF molecular weight forms: a cross-laboratory study comparing ristocetin cofactor, collagen-binding and mAb-based assays. J Thromb Haemost. 2012;10:1043–54. doi: 10.1111/j.1538-7836.2012.04729.x.
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