Myeloid BM precursors and thymic T-cell precursors in rescue animals are of donor origin.

On days 100 and 209, a single animal of the rescue group was killed. BM cells prepared from long bones were stained with CD90 (THY1), HIS48, and RT7.2FITC (detecting RT7^b-positive donor cells). As shown in panel A, 100% of THY1⁺HIS48⁺ BM cells were of donor origin (RT7^b-positive). Thymic cells (prepared as described) were stained with CD4 (W3/25), CD8 (OX8), and RT7.2 FITC. As shown in panel B, 99% of CD4⁺CD8⁺ thymic cells were of RT7^b allotype.