Development of H-Y, NuSAP1, and CHAF1b antibodies and IgG levels. A total of 6 patients were followed longitudinally after transplantation. Antibody intensities against NuSAP1, CHAF1b, H-Y (namely DDX3Y/X and UTY/X for patients 1-3, female donors with male recipients), and total IgG levels are plotted. The dotted vertical line represents cGVHD development. As observed, NuSAP1 antibodies peak between days 350 to 450. NuSAP1 Ab development does not correlate with total IgG levels, indicating that NuSAP1 Ab responses are specific and not due to general Ab augmentation.