Percentage of B-cell precursors among CD45⁺marrow cells (corrected for marrow cellularity and for M:E ratio).

Total, CD19^low (early), and CD19^high (late) B-cell precursors were quantitated (upper, middle, and lower panels, respectively). The corrected percentage of total B-cell precursors on day 30 was lower in patients who developed grade 2 to 4 acute GVHD by day 30 (n = 19) than in patients who did not do so (n = 52). The corrected percentage of total B-cell precursors on day 80 was lower in patients who developed grade 2 to 4 acute GVHD by day 90 (n = 54) than in patients who did not do so (n = 20). The corrected percentage of total B-cell precursors on day 365 was lower in patients who developed clinical extensive, chronic GVHD (n = 28) than in patients who developed no or limited chronic GVHD (n = 23) in the first posttransplantation year. The corrected percentages of the early precursors appear to be influenced by the GVHD and/or its treatment to a greater extent than the late precursors. The squares denote medians and the vertical bars denote 25th to 75th percentiles. In all 9 graphs, the difference between the 2 groups is significant (P < .05 for day 30; P < .01 for day 80;P < .001 for day 365).