Binding of patient-derived antibodies to single or combination alanine variants. (A) Heat map of the average binding of patient-derived antibodies to various CUB domain alanine variants, expressed as a percentage relative to wtADAMTS13 binding (n = 3). (B-H) Relative binding percentage of 7 patient-derived anti-CUB antibodies against single-alanine variants displayed on the structure of the CUB domains of ADAMTS13. (I) Patient-derived antispacer antibody (1-416) does not show any alterations in binding toward CUB domain alanine variants.