Suppression of B lymphopoiesis during GVHD. (A) Experimental scheme. TCD BM cells from (B6 × B6.SJL) F₁ (CD45.1⁺CD45.2⁺) mice with or without T cells from B6.SJL (CD45.1⁺) mice were transplanted to lethally irradiated CD45.2⁺ BDF₁ mice, and CD45.1⁺CD45.2⁺ donor BM–derived B and T lymphopoiesis was analyzed. (B-C) Flow cytometric analysis of B lymphopoiesis. (D) Donor BM-derived T lymphopoiesis. Kinetics of the frequency of CD4⁺ and CD8⁺ T cells in spleen. (E) Representative flow cytometric analysis of CD45.1⁺CD45.2⁺ thymic cells on day 21 after allo-HSCT. Cells were gated on CD45.1⁺CD45.2⁺ in each flow cytometric plot. Numbers in the plots represent the frequency of cells in adjacent gates. Data are representative of at least 3 independent experiments. Data are mean ± SE (n = 3 per group) in panels B and D. **P < .01. (F) Real-time RT-PCR on day 14 after allo-HSCT in sorted Lin⁻c-Kit⁺ cells or whole BM. In each group, sorted cells from 5-8 mice were pooled and total RNA was isolated. Data are from one of 2 experiments with similar results. ND indicates not detectable.