Immunologic clustering of donor-specific antibodies and clinical outcomes in kidney transplant recipients

Figure 2 illustrates a principal component analysis. Each point in this principal component analysis plot represents a donor-specific antibody (DSA)-positive kidney transplant recipient, color-coded by cluster membership, with shaded contours indicating the spatial density of patients within each group. The high-risk cluster (orange) demonstrates tight cohesion and distinct localization, characterized by patients with high mean fluorescence intensity (MFI), multiple DSAs, and mixed Class I and II sensitization. The intermediate-risk cluster (yellow) shows moderate density and spatial separation, predominantly representing Class II DSA patients with moderate immunologic burden. The low-risk cluster (green) occupies a well-isolated region with minimal overlap, encompassing patients with Class I-only DSA, low MFI, and favorable early graft function. While some overlap is observed between the high-risk and intermediate-risk clusters, the core density of each group remains distinct, indicating meaningful stratification. PCA: Principal component analysis.