Suppression of hematopoiesis during GVHD. Lethally irradiated BDF₁ mice were implanted with B6 TCD BM alone (BMT) or with additional splenic T cells (GVHD). Cell populations were assessed weekly from days 7 to 28 after allo-HSCT. (A) Total cells in BM, spleen, and thymus. (B) Mature lymphoid and myeloid cells in spleen (SPL) and BM. (C) Myeloid and lymphoid progenitor cells and hematopoietic stem cells. GMP indicates granulocyte/macrophage lineage-restricted progenitor; CMP, common myeloid progenitor; MEP, megakaryocyte/erythrocyte lineage–restricted progenitor; and KSL, c-Kit⁺Sca-1⁺Lin⁻. (D) Mature and immature erythropoietic cells. Data are mean ± SE from 1 of 2 to 4 experiments with similar results (n = 3 per group). *P < .05; **P < .01.