Neither recombinant CUB domains nor a CUB-1 synthetic peptide inhibit the cleavage of ULVWF under static conditions. ULVWF was incubated with barium-treated plasma in the presence of recombinant polypeptides (CUB-1, CUB-2, and CUB-1+2) or synthetic peptide (CUB1A) or its scrambled form (CUB1As) for 24 hours in the presence of 1.5 M urea. The cleavage of ULVWF was then assessed by 1% agarose gel electrophoresis and immunoblotting. Plasma ADAMTS13 cleaved the ULVWF multimers and the cleavage was not affected by pretreatment of plasma with any of the CUB polypeptides or synthetic peptides. The figure is representative of 3 separate experiments.