Laboratory Testing for von Willebrand Factor Collagen Binding (VWF:CB).

Von Willebrand disease (VWD) is reportedly the most common inherited bleeding disorder and can also arise as an acquired syndrome (AVWS). These disorders develop due to defects and/or deficiency of the plasma protein von Willebrand factor (VWF). Laboratory testing for the VWF-related disorders requires assessment of both VWF level and VWF activity, the latter requiring multiple assays because of the many functions carried out by VWF to help prevent bleeding. This chapter describes several protocols for assessment of VWF activity by means of VWF collagen binding (VWF:CB). These assays identify VWF activity by quantitative assessment of VWF protein adhesion to collagen or collagen peptides and subsequent immunological detection of the adhered VWF. The most commonly performed assays for VWF:CB comprise enzyme-linked immunosorbent assays (ELISA) and chemiluminescent assay (CLIA), as described in this chapter.