Comparison of residues located on the CUB domain of ADAMTS13 that are involved in binding of the spacer domain, and residues that are targeted by anti-CUB antibodies. Antibody epitopes as identified by HDX-MS or an alanine scan of the CUB domains, reveal that the residues overlap with the previously identified residues for maintaining the spacer-CUB interaction, but not with residues involved in the binding of the D4 domain of VWF. CUB domain PDB:7B01. Spacer domain PDB:6QIG.