The kinetics of peripheral reconstitution after BM or thymus grafts. CD45.2⁺ B6 Rag2γ_c⁻ mice were sublethally irradiated (600 rads) and grafted simultaneously with 2 × 10⁴ WT CD45.1⁺ LSKs, and a single thymus lobe from CD45.2⁺xCD45.1⁺ WT B6 neonatal mice and studied for 2 wk (A and B) and 1 mo later (C and D). (A and C) Percentages (histograms) and the phenotypes (dot plots) of thymus graft–derived (right) and BM-derived (left) cells in the grafted thymus. Top dot plots showing the CD4/CD8β profile, and bottom dot plots show TN cells. (B and D) Percentages (histograms) and CD44 expression (dot plots) of CD45.2⁺ T cells of thymus graft origin in the spleen. Results are from one mouse at each time point representative for the four mice studied.