Factors Associated With Death-Censored Allograft Loss in the Eculizumab-Treated +XM Cohort. A, BFXM; B and C, Class I + II donor-specific antibodies and IgG3 positivity were associated with death-censored allograft loss in eculizumab-treated patients. D, Death-censored allograft loss based on sum MFI DSA; E, Death-censored allograft loss in C1q negative and positive patients. BFXM indicates B-cell flow cytometric crossmatch; IgG, immunoglobulin; MFI, mean fluorescence intensity. *Hypothesis testing was between the class I + class II DSA group and the class I only and class II only groups combined.