We are testing two ELISA kits, one with a monoclonal antibody on the platelet directed at the portion of the VWF that binds the platelet and the other is the collagen binding assay. We often have trouble with our ristocetin cofactor assay. Do you, or does anybody, have any preferences or personal experience with either of these kits. Thanks, Anne Dagostino.
Anne, I’ve had some experience with the collagen binding assay (CBA), developed by Gradipore in Australia, and distributed by Life Diagnostics and others in the US. Microtiter plate wells are coated with type III collagen, which is sensitive to the abnormal von Willebrand factor (VWF) in type 2 von Willebrand disease (VWD). The assay distinguishes between VWD types 1 and 2 and is meant as a stable substitute for the ristocetin cofactor (VWF activity) assay, which is labor-intensive and suffers from poor CVs. The CBA is reliable provided the target collagen is stable from lot to lot.
I’m not as familiar with the first kit you dscribe and have farmed the question to an expert. When I hear from my friend, I will post an anwer, but meanwhile if anyone out there has experience, please reply here. Geo.