Domain structure of full-length VWF and rD′D3-FP. (A) Domain structure of native full-length VWF residues 1 to 2813, including propeptide D1D2 (blue) and the D′D3 domain (orange). Cysteines responsible for intra- and intermolecular dimerization are shown as yellow stars (C1099 and C1142 in the D3 domain; C2771, C2773, and C2811 in the CK domain). (B) rD′D3-FP monomer consisting of the propeptide domain D1D2 and the D′D3 domains of VWF N-terminally fused to human serum albumin (HSA; purple). This monomer dimerizes via its D3 domain to form the pro-rD′D3-FP dimer, which subsequently is processed by furin-catalyzed cleavage of the propeptide D1D2 to yield the final product, mature dimeric rD′D3-FP, as shown in panel C.