T-cell reconstitution by Delta1^ext-IgG-cultured cells transplanted with increasing doses of whole BM. (A) Lethally irradiated Rag^−/− recipients received 1 × 10⁵, 1 × 10⁶, or 1 × 10⁷ Ly5.1 BM cells augmented with 2.5 × 10⁷ Ly5.2 Delta1^ext-IgG-cultured cells. FACs analysis and CBCs were performed on blood samples obtained at various times after HCT. Panels A to E show the absolute number of cells expressing CD3⁺, CD4⁺, CD8⁺, CD19⁺, and Gr1⁺ cells contained in blood samples from Rag^−/− recipients that received, respectively, 1 × 10⁵, 1 × 10⁶, or 1 × 10⁷ Ly5.1 BM cells augmented with 1 × 10⁷ Ly5.2 Delta1^ext-IgG-cultured cells. Graphs depict engraftment from BM cells (▵) and engraftment from Delta1^ext-IgG-cultured cells (•). Data represent the mean plus or minus SEM of 3 separate experiments (n = 10-15).