CUB-NGLY variants reduce the binding of nonspacer targeting antibodies. (A) Heat map of reactivity of plasma from patients with iTTP with wtADAMTS13 and CUB-NGLY variants (n = 1). (B) ELISA binding result of patient antibodies against spacer protective mutants (NGLY3 and 5ALA) ± CUB-NGLY variants. All binding is relative to wtADAMTS13. Significance was determined using an ordinary 1-way analysis of variance using a Tukey multiple comparison test, with a single pooled variance. ∗∗∗∗P < 0.0001.